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galacsi
2007-Sep-18, 09:34 PM
FROM NEREID : "Crudely, how does your PC+internet 'work', in the sense of you successfully posting here, if SR is such a comprehensive failure?"

Yes I would like to know ? Because , may be , QM was a prerequisite for building the chips that power my PC , and I am not even sure , but I don't see what SR has to do in this adventure ! I really curious !

It is Nereid who formulated this rather provocative question , but of course , anybody is welcome to answer !

Nereid
2007-Sep-19, 05:49 AM
QED (http://en.wikipedia.org/wiki/Quantum_electrodynamics)* (quantum electrodynamics) is the most accurate physical theory (http://en.wikipedia.org/wiki/Precision_tests_of_QED)* we have, today.

There are many, many aspects of the way your PC+internet works that rely upon QED being a sufficiently accurate description of 'the rules of the universe'; not only in the PC chips (semi-conductor band structure (http://en.wikipedia.org/wiki/Band_structure)*, for example) but also the physical equipment used in the networks that provide transport for the internet (this includes clock synchronisation) and even the phosphors in CRT monitors (for those who still use them).

And what does QED have to do with special relativity (SR)?

Everything - QED incorporates SR; in the words of the Encyclopaedia Britannica (http://concise.britannica.com/ebc/article-9062163/quantum-electrodynamics) "QED is a relativistic theory in that Albert Einstein's theory of special relativity is built into each of its equations."

So, if your alternative textbook of physics includes something to the effect that SR is a comprehensive failure, then you have rather a lot of explaining to do ... such as replacing QED.

*One should always tread wikipedia with some caution, but for the purposes of this post, I think the entries are good enough.

astromark
2007-Sep-19, 08:12 AM
Excellent perspective and a thoughtful response. It is good to question the very foundation of belief. For only by testing and explanation does an understanding of these things evolve. My understanding is always evolving as modification to previously held doctrine is replaced with a fresh explanation of new data. Thanks Nereid and galacsi...
I have joined this conversation because elsewhere in this forum I was criticized for having a incomplete point of view (different).. Your explanations of this subject mater has helped me move forward.
I note the small print warning us of incorrect or misleading things found on Wiki...

dhd40
2007-Sep-19, 01:26 PM
And what does QED have to do with special relativity (SR)?

Everything - QED incorporates SR; in the words of the Encyclopaedia Britannica (http://concise.britannica.com/ebc/article-9062163/quantum-electrodynamics) "QED is a relativistic theory in that Albert Einstein's theory of special relativity is built into each of its equations."



Yes, my layman´s understanding of QED is (from Richard P.Feynman´s >>QED - The strange theory of light and matter<<) that it explains everything except gravity and nuclear physics. Therefore, QED incorporates SR (as Nereid states), but not GR (General Relativity). We´re still waiting for a unifying theory, aren´t we?

galacsi
2007-Sep-21, 01:46 PM
Nereid there is a problem , it is that i don't buy your answer , not at all.

Let's look at the computer history. (Very simplified , from memory )

* And first there was the abacus.
* There came the Pascal's contraption.
* Then the differential machine.
* Then the first mechanical calculator

And there is absolutely no need of SR to make these devices work.

* And no come the 20th century :
* The electromechanical calculator
* DIODE and TRIODE are invented. (Mean the glassy one)
* First electronic calculators.
* Transistor is invented and replace the triode. Silicon begin its reign.
* Then printed circuits , then integrated circuits . . . . .

And where Special relativity has been used in all this progress ? Seriously ?

One can see the advantage of QM because it has been used to better understanding of transistors , diodes. . . . And of course without QM , no laser , and no CD and no DVD.

But QED ? IMO It is a purely academic theory which had no impact on Invention and fabrication of my Laptop. And idem with routers , switches , optical fibers and so on.

So the existence of technology is not a proof for this theory.

I think your argument is a kind of "Anthropic principle". As I said at the beginning I don't buy it.

mugaliens
2007-Sep-21, 02:06 PM
Yeah, well, as Intel scales their QuadCore processers down to the following specs:

8 MB of L2 cache
1333 MHz front-side bus

(sorry, folks - I have to wipe up some drool...)

They're having to consider a number of effects.

One, with their 65 nm dies has to do with quantum effects.

The other, more particularly with the upcoming 45 nm dies has to do with the effects of cosmic radiation.

Yes, it appears that cosmic radiation has the ability to interfere with your leisure activities, and if certain computing redundancies aren't built in, the 45 nm processesor will encounter the occasional cosmic radiation-induced hang-up.

Not something Intel would like to tell the planet, mind you, as the smaller and less energy-using dies are one of their biggest selling points against AMD...

Regardless, I think we're soon to enter an era of cosmic ray shielding for our computers. Leaded-steel casings, anyone?

Don't know what it would take. As for me, I'm happy living a mile underground (just kidding).

Nereid
2007-Sep-21, 03:17 PM
Nereid there is a problem , it is that i don't buy your answer , not at all.

Let's look at the computer history. (Very simplified , from memory )

* And first there was the abacus.
* There came the Pascal's contraption.
* Then the differential machine.
* Then the first mechanical calculator

And there is absolutely no need of SR to make these devices work.

* And no come the 20th century :
* The electromechanical calculator
* DIODE and TRIODE are invented. (Mean the glassy one)
* First electronic calculators.
* Transistor is invented and replace the triode. Silicon begin its reign.
* Then printed circuits , then integrated circuits . . . . .

And where Special relativity has been used in all this progress ? Seriously ?

One can see the advantage of QM because it has been used to better understanding of transistors , diodes. . . . And of course without QM , no laser , and no CD and no DVD.

But QED ? IMO It is a purely academic theory which had no impact on Invention and fabrication of my Laptop. And idem with routers , switches , optical fibers and so on.

So the existence of technology is not a proof for this theory.

I think your argument is a kind of "Anthropic principle". As I said at the beginning I don't buy it.Let's take another look at the post, in a thread in the About BAUT section, from which the OP is quoting. It's here (http://www.bautforum.com/1071138-post78.html), and in full is as follows:
The nature of astronomy (etc) as science

Several posts in this thread touch on a related topic: what is the nature of astronomy and space science (and astrophysics, and cosmology) as sciences?

BAUT has quite a few threads on this, and related, topics; some date from before the BABB/UT merger, some are in the ATM section, some in the Q&A section, and some in other explicitly science-based sections. There are also quite a few sub-threads, in these sections.

At least some part of the concerns expressed in the OP are likely due to quite different perspectives on what 'astronomy as a science' is; for example, in many posts by at least one BAUT member, there is (to me) clear inconsistency sufficient to make the main point of the post essentially illogical*.

This is, I think, quite serious ... not much different from the apparent absurdity of an ATM claim of a comprehensive failure of Special Relativity posted in this forum!^

Perhaps we should devote several, hopefully quite long, threads to examining just what accepting 'astronomical observations' actually entails (other than 'here's the readout from {insert instrument here}')? In these threads we may look, hard, at just how much modern physics is threaded through the chain leading to a reported result, perhaps by looking at the relatively boring Section 2's of many published papers (these are, often, the parts of the papers which describe how the data were obtained, data which later are analysed, and from which conclusions are drawn).

*To give one (grossly?) oversimplified example: a result obtained by VLBI used to suggest that GR has serious problems, without acknowledging that if the problems (with GR) were so severe then the methods used (VBLI) to produce the results would render them untenable!
^Crudely, how does your PC+internet 'work', in the sense of you successfully posting here, if SR is such a comprehensive failure?The context is science, and, more narrowly, the explanation of how things work.

By contrast, your post (which I have quoted) is about whether things work and how one can make something which works.

The first (whether things work), recast, would be '(some) birds fly, therefore birds know all about fluid dynamics, gravity, etc'. True, some birds do, and can, fly; within the scope of my About BAUT thread post, the question is how do you account for the flight of birds?

The second (how you can make something which works), recast, would be 'I made this kite, it flies very well (provided it's windy enough), therefore I know all about fluid dynamics, gravity, etc'. True, your kite may fly very well, and you may be able to write down detailed instructions so that other people could also build kites which fly just as well; within the scope of my About BAUT thread post, the question is how do you account for the flight of your kites?

There's another aspect which should be mentioned: the level of 'how {thing} works'. Take just one small part of the 'working' of your PC. In principle, you could build some mechanical equivalent of the CPU chip, a monster descendant of a Babbage machine perhaps, that would do the same thing as the CPU chip (albeit a great deal more slowly, and, very likely, much less reliably). This computational aspect of the operation of your PC's CPU chip does not require any physics to understand, or explain - all you need is some relatively simple maths plus a great deal of detail.

So, to the point: how does the CPU chip in your PC work? In modern (condensed matter, or solid state) physics, the underlying theory is QED, which has SR baked into its bones. If you declare that SR is a comprehensive* failure, you have, in one fell swoop, un-explained how the CPU chip in your PC works. Your mission, should you choose to accept it, is to explain it anew.

And that's just one example; there are many, possibly hundreds, of examples of things that go directly to make up your ability to post on BAUT. To repeat, the explanation for how those things work incorporates SR^.

And to bore readers silly, may I repeat that the scope of my statement is science.

I trust that this clarifies things somewhat; if not, please ask more questions! :)

*It doesn't have to be 'comprehensive', it need be 'the domain of QED', or 'the domain of international clock synchronisation', or ...
^Perhaps a more direct example might be the use of clocks in the telecoms networks that the internet runs over, both in how those clocks work, and how precisely Telstra, BT, AT&T, DT, China Telecom, etc need to synchronise those clocks to keep the networks running.

Celestial Mechanic
2007-Sep-21, 03:31 PM
Nereid there is a problem , it is that I don't buy your answer , not at all.

Let's look at the computer history. (Very simplified , from memory )

* And first there was the abacus.
* There came the Pascal's contraption.
* Then the differential machine.
* Then the first mechanical calculator

And there is absolutely no need of SR to make these devices work.And these devices are irrelevant to Nereid's original question, which was:

Crudely, how does your PC+internet 'work', in the sense of you successfully posting here, if SR is such a comprehensive failure?{Emphasis mine}
I know of no one who ever accessed the internet with an abacus or a mechanical calculator, do you? This is called "evading the question".

* And now comes the 20th century :
* The electromechanical calculator
* DIODE and TRIODE are invented. (Mean the glassy one)
* First electronic calculators.
* Transistor is invented and replace the triode. Silicon begin its reign.
* Then printed circuits , then integrated circuits . . . . .

And where Special relativity has been used in all this progress ? Seriously ?
Not directly, but implicitly for reasons I'll get to below.

One can see the advantage of QM because it has been used to better understanding of transistors , diodes. . . . And of course without QM , no laser , and no CD and no DVD.

But QED? IMO It is a purely academic theory which had no impact on Invention and fabrication of my Laptop. And idem with routers , switches , optical fibers and so on. So the existence of technology is not a proof for this theory. I think your argument is a kind of "Anthropic principle". As I said at the beginning I don't buy it.
Nereid's original question did not mention QED, it mentioned SR. Nereid's answer to your question mentions QED because it is the result of the marriage of EM and QM. It incorporates SR because EM is a special relativistic theory from the ground up. Oh, sure you can write it with vector fields and potentials plus a scalar potential, but it does not really begin to make sense until it is written as a four-vector potential and an anti-symmetric tensor field.

The first forty or so years of electromagnetism involved much floundering about trying to make it fit into Newtonian mechanics; Einstein showed that it was Newtonian mechanics that had to be amended and extended so that it would fit with electromagnetism. Now, why do you think that SR is such a comprehensive failure? :think:

01101001
2007-Sep-21, 03:56 PM
Now, why do you think that SR is such a comprehensive failure?

Just, if galacsi, or anyone, feels compelled to assert and argue that SR is a comprehensive failure, a happier place for that is in Against the Mainstream.

Here it makes sense to ask if SR is a comprehensive failure. (No.) Or, to ask about what Nereid said about computers and the Internet. Good questions. I don't think they need to be illuminated by galacsi's possible conjectures about SR, fascinating as they might be.

John Mendenhall
2007-Sep-21, 04:07 PM
I think your argument is a kind of "Anthropic principle". As I said at the beginning I don't buy it.

Then you should stay off airplanes, 'cause the radar doesn't work right if there isn't a teeny-tiny little SR contraction of the microwave cavity in the direction of motion.

galacsi
2007-Sep-21, 07:08 PM
Then you should stay off airplanes, 'cause the radar doesn't work right if there isn't a teeny-tiny little SR contraction of the microwave cavity in the direction of motion.

So Einstein did invent the Radar ! What a man !

Seriously i ask you to show me evidence of this rather astonishing claim ! Maths are not forbidden.

galacsi
2007-Sep-21, 07:14 PM
And these devices are irrelevant to Nereid's original question, which was:
{Emphasis mine}
I know of no one who ever accessed the internet with an abacus or a mechanical calculator, do you? This is called "evading the question".

Not directly, but implicitly for reasons I'll get to below.

Nereid's original question did not mention QED, it mentioned SR. Nereid's answer to your question mentions QED because it is the result of the marriage of EM and QM. It incorporates SR because EM is a special relativistic theory from the ground up. Oh, sure you can write it with vector fields and potentials plus a scalar potential, but it does not really begin to make sense until it is written as a four-vector potential and an anti-symmetric tensor field.

The first forty or so years of electromagnetism involved much floundering about trying to make it fit into Newtonian mechanics; Einstein showed that it was Newtonian mechanics that had to be amended and extended so that it would fit with electromagnetism. Now, why do you think that SR is such a comprehensive failure? :think:

Like they say in my country lingo : "Vous faites l'âne pour avoir du foin"

I did not say "That SR is such a comprehensive failure".

Answering Nerid sentence I just say computers and internet existence cannot be taken as proof of SR. Rather clear no ?

galacsi
2007-Sep-21, 07:16 PM
Just, if galacsi, or anyone, feels compelled to assert and argue that SR is a comprehensive failure, a happier place for that is in Against the Mainstream.

Here it makes sense to ask if SR is a comprehensive failure. (No.) Or, to ask about what Nereid said about computers and the Internet. Good questions. I don't think they need to be illuminated by galacsi's possible conjectures about SR, fascinating as they might be.

Ha ha binary man has mounted his old horse again !

galacsi
2007-Sep-21, 07:48 PM
The context is science, and, more narrowly, the explanation of how things work.

Was not me who write the OP ? I choose to answer you bottom of page note N°2 , not all your post.

As I can be a practical man , I choose to answer it this way.


By contrast, your post (which I have quoted) is about whether things work and how one can make something which works.
. . . .

So, to the point: how does the CPU chip in your PC work? In modern (condensed matter, or solid state) physics, the underlying theory is QED, which has SR baked into its bones. If you declare that SR is a comprehensive* failure, you have, in one fell swoop, un-explained how the CPU chip in your PC works.

And you can explain everything this way ! Cause QED is a theory of everything !

By example , I am currently cooking , while writing this post.

Transformations of food in my saucer pan are in fact chemistry and chemistry is in fact explained by QM .

So is the fact that i can make a watercress soup a proof of QM ? And of QED ? This is silly , is not 'it ?

Also I am not sure all these stories about Clocks Synchronization , GPS , . . . prove anything.
But first , I don't want to infuriate this brave Binary man who is so fast to detect ATM contamination in our intellectual food , and frankly I Don't think I have the level to discuss it seriously. So I reserve my opinion with a negative prejudice.

IMO seems we don't live in the same world : You are in the etherical realms of Academia and me Down on the country !

EDG
2007-Sep-21, 08:31 PM
The first (whether things work), recast, would be '(some) birds fly, therefore birds know all about fluid dynamics, gravity, etc'. True, some birds do, and can, fly; within the scope of my About BAUT thread post, the question is how do you account for the flight of birds?

I remember that there was something in maths that boggled me. I can't recall the specifics, just that the only way to model certain very common real-world things (I think it was a wave function??) was by using hyperbolic functions (sinh, tanh etc). The problem that got me was that to solve these functions, you needed to use complex numbers, which have an imaginary component. So here we have real things behaving perfectly well, yet to do so they require numbers that don't really exist. Bwuh?!

I guess the problem is more with our mathematical system, which has this somewhat kludgy 'complex number' thing for roots of negative numbers. So the numbers aren't really "imaginary", it's just that we can't think of a better way to express them. I think.

01101001
2007-Sep-21, 08:34 PM
Ha ha binary man has mounted his old horse again !

Glad it pleases you. Vigilant, am I not? Don't take offense. It wasn't addressed so very much at you. I'm sure you know better than to assert ATM ideas in Q&A, even when prodded. It was more for others, maybe even new people, people who might not have made the acquaintance of my handsome horse, who might see the question as an opportunity to expound.

Frankly, more to the point, I wish people would avoid asking such platform questions in Q&A, at least without calling for the answer elsewhere. Then I could leave my splendid steed to enjoy his stud work.

Nereid
2007-Sep-21, 10:15 PM
Was not me who write the OP ? I choose to answer you bottom of page note N°2 , not all your post.

As I can be a practical man , I choose to answer it this way.


. . . .


And you can explain everything this way ! Cause QED is a theory of everything !

By example , I am currently cooking , while writing this post.

Transformations of food in my saucer pan are in fact chemistry and chemistry is in fact explained by QM .

So is the fact that i can make a watercress soup a proof of QM ? And of QED ? This is silly , is not 'it ?

Also I am not sure all these stories about Clocks Synchronization , GPS , . . . prove anything.
But first , I don't want to infuriate this brave Binary man who is so fast to detect ATM contamination in our intellectual food , and frankly I Don't think I have the level to discuss it seriously. So I reserve my opinion with a negative prejudice.

IMO seems we don't live in the same world : You are in the etherical realms of Academia and me Down on the country !(my bold)

That does seem to be so, galacsi.

But this is BAUT, an internet discussion forum that is avowedly science-based, and focussed on astronomy and space science.

If all you wish to do is live in the country, enjoy fine wine and eat fine food, surf the internet, and wonder about the glorious night sky in purely non-scientific ways, then why hang out here?

I mean, regarding the collective results of the intellectual endeavours of the millions of folk - scientists and non - whose lives have resulted in your present material comfort and good health, that you care not one jot is a mutual feeling, and completely irrelevant in any case.

Your PC, and its internet connection, will work just fine, whatever you feel about BAUT, Nereid, the digital guy, EDG_, CM, JM, SR, the tens of thousands of scientists and engineers whose efforts resulted in that PC and internet connection, and so on.

So, again, why do you hang out here?

galacsi
2007-Sep-21, 10:53 PM
(my bold)

That does seem to be so, galacsi.

But this is BAUT, an internet discussion forum that is avowedly science-based, and focussed on astronomy and space science.

If all you wish to do is live in the country, enjoy fine wine and eat fine food, surf the internet, and wonder about the glorious night sky in purely non-scientific ways, then why hang out here?

I mean, regarding the collective results of the intellectual endeavours of the millions of folk - scientists and non - whose lives have resulted in your present material comfort and good health, that you care not one jot is a mutual feeling, and completely irrelevant in any case.

Your PC, and its internet connection, will work just fine, whatever you feel about BAUT, Nereid, the digital guy, EDG_, CM, JM, SR, the tens of thousands of scientists and engineers whose efforts resulted in that PC and internet connection, and so on.

So, again, why do you hang out here?

You really dont want to understand what i have been saying from the beginning : Your computer and internet demonstration prove nothing at all. You are wrong.
This supposed demonstration is just demagogy.

It does not mean SR is wrong. SR is supported by experiments and if you believe SR is wrong show me your evidence. I Mean scientific evidence.

Feel reassured , I have a passion for Astronomy which goes further than wondering at night sky. And I think you are patronizing in the above post.

And I am here in this thread to just say what I am Thinking.To bad if it does not please you.

That the problem with a forum , people frequently disagree with you. In fact when they agree they rarely feel the need to write a post to say it.

I am just playing an other tune that the one you are accustomed to.

Nereid
2007-Sep-21, 11:33 PM
You really dont want to understand what i have been saying from the beginning : Your computer and internet demonstration prove nothing at all. You are wrong.
This supposed demonstration is just demagogy.FWIW, I did not set out to 'prove' anything ... indeed, 'proof' is not part of any self-respecting scientist's vocabulary.
It does not mean SR is wrong. SR is supported by experiments and if you believe SR is wrong show me your evidence. I Mean scientific evidence.

Feel reassured , I have a passion for Astronomy which goes further than wondering at night sky. And I think you are patronizing in the above post.

And I am here in this thread to just say what I am Thinking.To bad if it does not please you.

That the problem with a forum , people frequently disagree with you. In fact when they agree they rarely feel the need to write a post to say it.

I am just playing an other tune that the one you are accustomed to.Whatever.

Here's what I said, expressed in a somewhat different way: the scientific (physics) theory that underlies an explanation of how your PC+internet works incorporates SR in such a way that removing SR results in confusion (at best) or nonsense (at worst). IF you are interested to know how, and why, that is so, then I (and many other BAUT members) would be only too happy to patiently explain, point you to library resources, recommend university courses for you to enroll in, and so on.

OTOH, if you could care less about a scientific approach to understanding all that you see (feel, touch, hear, etc), then, again, I have to ask: why do you hang out here?

Exposed
2007-Sep-22, 04:38 AM
I have to point out a few flaws here. The way a PC or internet works really has nothing to do with Relativity, nor is it a crucial theory that underlies the development of computer technology over the last century (but quantum effects will play a huge role in the next century).

The basic premise behind CPU operations is boolean logic in a binary system. This can be performed incredibly fast when implemented among electrical pathways, but it is not necessary limited to such medium. I remember a tech magazine stating that if you had enough elephants and rope, you can position them and have them respond to a rope pull in a logical way to make rudimentary computations. The first programmable digital computer was composed of only vacuum tubes and large wires. It wasn't until the invention of the transistor did computational power increase exponentially to what it is today, and even then all your CPU is doing is performing billions of "add operations" per second no different than what the ENIAC did half a century ago.

Back in the 60's when the "Old Internet" was just a military project to maintain communications in case of a nuclear attack, the premises of that era still remains the same today even though technology has changed. Bits of information follow the 7 layers of the OSI model when routed from Point A to Point B, and routers still use OSPF/RIP or whatever distance vector protocols ....all just using pulses of electricity to represent bits of information.

I really don't see how special relativity played an underlying role in both cases above.

The manufacturing process however, is rapidly approaching a physical limit. There is only so much transistors and gates that can be packed onto a wafer. There will eventually be a point where transistors cannot get any smaller (15-20 years away) and other exotic means of manipulating atoms involving quantum effects will be utilized. But don't confuse the manufacturing process as proof of the underlying science for the base concept.

If Einstein died without releasing his papers on relativity, computer technology still would exist and improve without them. The invention of the transistor was not inspired by relativity and the manufacturing process would not have to account for quantum mechanical effects (which relativity did not quite contribute to) until much, much later.

Lastly, cosmic rays and its effects on data has been known for decades. It's really only significant for mission critical applications, which is why ECC memory is specifically manufactured for that purpose. A single cosmic ray can damage the molecules in a memory location, changing the data and giving a false result. ECC memory corrects those errors via a parity check. This doesn't seem like a good example to equate PC technology with special relativity.

galacsi
2007-Sep-22, 07:51 AM
FWIW, I did not set out to 'prove' anything ... indeed, 'proof' is not part of any self-respecting scientist's vocabulary.Whatever.

This is Fun :question: : Proving their ideas is just reserved to Atmers in this forum.



OTOH, if you could care less about a scientific approach to understanding all that you see (feel, touch, hear, etc), then, again, I have to ask: why do you hang out here?

Whatever.

Happily , out of SR ,QED , Strings .... there are many interesting things in this site.

For instance :

http://www.universetoday.com/2007/09/21/more-martian-cave-entrances-discovered/

http://www.universetoday.com/2007/09/21/martian-southern-cap-is-mostly-water-ice/

Real astronomy in the making ! Exciting isn't it ?

And threads about space exploration , astrophotography ...

http://www.bautforum.com/space-exploration/64444-new-high-velocity-photonic-thruster.html

http://www.bautforum.com/astrophotography/64961-solar-pillar.html

And much more !

So Nereid :rolleyes:

Nereid
2007-Sep-23, 04:09 PM
I have to point out a few flaws here. The way a PC or internet works really has nothing to do with Relativity, nor is it a crucial theory that underlies the development of computer technology over the last century (but quantum effects will play a huge role in the next century).

The basic premise behind CPU operations is boolean logic in a binary system. This can be performed incredibly fast when implemented among electrical pathways, but it is not necessary limited to such medium. I remember a tech magazine stating that if you had enough elephants and rope, you can position them and have them respond to a rope pull in a logical way to make rudimentary computations. The first programmable digital computer was composed of only vacuum tubes and large wires. It wasn't until the invention of the transistor did computational power increase exponentially to what it is today, and even then all your CPU is doing is performing billions of "add operations" per second no different than what the ENIAC did half a century ago.

Back in the 60's when the "Old Internet" was just a military project to maintain communications in case of a nuclear attack, the premises of that era still remains the same today even though technology has changed. Bits of information follow the 7 layers of the OSI model when routed from Point A to Point B, and routers still use OSPF/RIP or whatever distance vector protocols ....all just using pulses of electricity to represent bits of information.

I really don't see how special relativity played an underlying role in both cases above.

The manufacturing process however, is rapidly approaching a physical limit. There is only so much transistors and gates that can be packed onto a wafer. There will eventually be a point where transistors cannot get any smaller (15-20 years away) and other exotic means of manipulating atoms involving quantum effects will be utilized. But don't confuse the manufacturing process as proof of the underlying science for the base concept.

If Einstein died without releasing his papers on relativity, computer technology still would exist and improve without them. The invention of the transistor was not inspired by relativity and the manufacturing process would not have to account for quantum mechanical effects (which relativity did not quite contribute to) until much, much later.

Lastly, cosmic rays and its effects on data has been known for decades. It's really only significant for mission critical applications, which is why ECC memory is specifically manufactured for that purpose. A single cosmic ray can damage the molecules in a memory location, changing the data and giving a false result. ECC memory corrects those errors via a parity check. This doesn't seem like a good example to equate PC technology with special relativity.I thought I'd covered this point earlier, but it seems it's still not clear.

First, the main level at which relativity is important for how your PC+internet works is the physical - the nitty-gritty of band structures in the semiconductors in the motherboard chips, for example, or the atomic transition(s) that are the heart of rubidium clocks (so widely used by telecoms companies), or the optical amplifiers used for signal regeneration in fibre optics cables. Note that these are just three examples; there are, no doubt, potentially hundreds of such examples.

Second, the point I'm making is about science, not really engineering. At the engineering level, you don't need to know much about why doping a fibre with erbium works (in terms of amplifying the optical signal), to take just one example; however, to understand it from the POV of the underlying physics, you do.

Third, in terms of a scientific understanding of semi-conductor band structures or rubidium transitions, or ... you also need to have a robust, reliable view of the nature of science. As I have said, a great many times, I think such a view must give centrality to theories - in science (or at least physics) we use theories to explain, or describe, everything*. In the case of your PC+internet, the theory which underlies how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work is QED. QED incorporates SR.

Turning this around, if you claim SR to be a comprehensive failure, you have to provide a new explanation for how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work ... an explanation that does not include QED (well, you 'have to' if you are approaching this in a scientific manner).

Do you still have questions, galacsi?

Perhaps it would help if we took just one example, and showed how QED is essential for understanding how the thing works?

Or how QED so intimately depends upon (incorporates) SR?

Or how well QED stacks up against the relevant experimental and observational results?

*Within the domain physics claims to have pertinence; re your PC+internet, that certainly includes how semiconductor ICs, rubidium clocks, and optical amplifiers work.

galacsi
2007-Sep-23, 09:36 PM
Do you still have questions, galacsi?




This dialog of deaf is boring me to death !

Nereid
2007-Sep-23, 09:53 PM
Do you still have questions, galacsi?This dialog of deaf is boring me to death !Here is the question, that you posed, in the OP: "Yes I would like to know ? Because , may be , QM was a prerequisite for building the chips that power my PC , and I am not even sure , but I don't see what SR has to do in this adventure ! I really curious !"

In a single line* sentence: a satisfactory, quantitative, scientific explanation of why your PC+internet works the way it does requires a theory called QED, which theory incorporates SR; remove SR and you can no longer explain how your PC+internet works.

Perhaps your question could be re-phrased? Perhaps you didn't understand the answer? In any case, I do hope that you do not die anytime soon (whether from boredom or any other cause).

*Maybe it takes one and a half lines.

Jens
2007-Sep-26, 06:26 AM
Like they say in my country lingo : "Vous faites l'âne pour avoir du foin"


I'm curious about what that means. I know literally, it means "you play the *** to get hay". But what is the figurative meaning? Something like "you are provoking me"?

Disinfo Agent
2007-Sep-26, 01:41 PM
I remember that there was something in maths that boggled me. I can't recall the specifics, just that the only way to model certain very common real-world things (I think it was a wave function??) was by using hyperbolic functions (sinh, tanh etc). The problem that got me was that to solve these functions, you needed to use complex numbers, which have an imaginary component.You probably don't really need them. It's just simpler to do when you use them.

I don't know, I haven't followed this conversation down to the "nitty-gritty", but here on the outside looking in it sure looks like galacsi has made a valid question (as confirmed by Exposed), and his critics here have done nothing so far but evading the question, attacking him personally, and waffling.

Kwalish Kid
2007-Sep-26, 01:53 PM
You probably don't really need them. It's just simpler to do when you use them.

I don't know, I haven't followed this conversation down to the "nitty-gritty", but here on the outside looking in it sure looks like galacsi has made a valid question (as confirmed by Exposed), and his critics here have done nothing so far but evading the question, attacking him personally, and waffling.
You should look closer.

The original question was one about the science of the overall operation of personal computers and the internet and how SR is involved. Fairly direct answers were given to this question.

Next, galacsi (and later Exposed) shifted the question to mostly the mathematical theory of computing rather than address the actual physics that are required to create a physical system that might be said to operate in such a way that it implements some kind of mathematical computing machine. As was previously addressed, the current technology that implements computing machines relies on QED, and thus on SR. Additionally, the technology that allows communication over the internet also relies on this science.

Disinfo Agent
2007-Sep-26, 02:26 PM
The original question was one about the science of the overall operation of personal computers and the internet and how SR is involved. Fairly direct answers were given to this question.Such as?


Next, galacsi (and later Exposed) shifted the question to mostly the mathematical theory of computing [...]It was not a shift. They were arguing that (contrary to what Nereid had claimed) SR has no connection with whether computers work or not.


As was previously addressed, the current technology that implements computing machines relies on QED, and thus on SR.Yeah, it relies on the QM part of QED. No one has convincingly shown that the SR part of it is also relevant. If it isn't, then "Well, they're based on QED and QED includes SR" is a fallacy of association.

John Mendenhall
2007-Sep-26, 02:27 PM
So is the fact that i can make a watercress soup a proof of QM ? And of QED ? This is silly , is not 'it ?



Actually, it is a demonstration of both. What we think of as ordinary chemistry (and cooking, if you really want to irritate chemists, just remind them that most chemistry is a kind of cooking) actually involves minute transformations of the E=Mc^2 variety, although in the atomic shells, not in the nucleus. As I recall, Asimov discusses this in one of his books.

Disinfo Agent
2007-Sep-26, 02:29 PM
You might still be able to cook in a Newtonian universe. The fact that you're able to cook proves precious little about whether relativity is valid or not.

John Mendenhall
2007-Sep-26, 02:52 PM
I have to point out a few flaws here. The way a PC or internet works really has nothing to do with Relativity, nor is it a crucial theory that underlies the development of computer technology over the last century (but quantum effects will play a huge role in the next century).



Used any tunnel diodes lately? That quantum mechanical applied technology is at least 40+ years old.




If Einstein died without releasing his papers on relativity, computer technology still would exist and improve without them. The invention of the transistor was not inspired by relativity and the manufacturing process would not have to account for quantum mechanical effects (which relativity did not quite contribute to) until much, much later.



True, but your and my current machines account for it. As far as I can see, Nereid's claim is correct.




Lastly, cosmic rays and its effects on data has been known for decades. It's really only significant for mission critical applications, which is why ECC memory is specifically manufactured for that purpose. A single cosmic ray can damage the molecules in a memory location, changing the data and giving a false result. ECC memory corrects those errors via a parity check. This doesn't seem like a good example to equate PC technology with special relativity.



Well, all computers are affected by cosmic rays, and cosmic rays don't reach the ground very well without relativistic time dilation. And even good memory correction only greatly reduces the probability of failure; one super energetic cosmic ray, or two or more simultaneous hits, can bring it down. As I recall, the strongest cosmic rays have the energy of a 95 mph fastball.

Totally off-topic and irrational blue sky aside: I wonder if cosmic rays could do the quantum pair trick and travel as if the universe was super-conductive?

Kwalish Kid
2007-Sep-26, 03:09 PM
It was not a shift. They were arguing that (contrary to what Nereid had claimed) SR has no connection with whether computers work or not.
"Computers" in the sense of idealized machines that carry out effective computations do not rely on any particular physical theory. However, this is irrelevant to the question at hand. The server on which this board runs definitely relies upon SR.

Yeah, it relies on the QM part of QED. No one has convincingly shown that the SR part of it is also relevant. If it isn't, then "Well, they're based on QED and QED includes SR" is a fallacy of association.
Perhaps it relies on the QM part that relies on SR?

Disinfo Agent
2007-Sep-26, 03:36 PM
"Computers" in the sense of idealized machines that carry out effective computations do not rely on any particular physical theory. However, this is irrelevant to the question at hand.No, that is precisely the question at hand.


The server on which this board runs definitely relies upon SR.How so?


Perhaps it relies on the QM part that relies on SR?And perhaps it doesn't.

01101001
2007-Sep-26, 03:36 PM
They were arguing that [...]

They got their answer from out of the mainstream.

That they are arguing against the mainstream answer is to me a rather bold hint that their questioning wasn't sincere and instead was merely a launching platform for the statements they wished to issue.

The Q&A opportunities dried up many many articles ago, no? Or, is there an unanswered question remaining on the table?

Disinfo Agent
2007-Sep-26, 03:40 PM
Used any tunnel diodes lately? That quantum mechanical applied technology is at least 40+ years old.And what does it have to do with SR, specifically?


That they are arguing against the mainstream answer is to me a rather bold hint that their questioning wasn't sincere and instead was merely a launching platform for the statements they wished to issue.They're "arguing against the mainstream answer"? Or are they just arguing against the overcomfidence of the defenders of the mainstream?

01101001
2007-Sep-26, 03:43 PM
They're "arguing against the mainstream answer"?

Yes.


Or are they just arguing against the overcomfidence of the defenders of the mainstream?

No. You had it right the first time.

Are there any other open questions?

Disinfo Agent
2007-Sep-26, 03:46 PM
Interesting: dogma, waffling and ad hominems... zero evidence! :rolleyes:

Nereid
2007-Sep-26, 03:52 PM
Disinfo Agent, did you read this post?
I thought I'd covered this point earlier, but it seems it's still not clear.

First, the main level at which relativity is important for how your PC+internet works is the physical - the nitty-gritty of band structures in the semiconductors in the motherboard chips, for example, or the atomic transition(s) that are the heart of rubidium clocks (so widely used by telecoms companies), or the optical amplifiers used for signal regeneration in fibre optics cables. Note that these are just three examples; there are, no doubt, potentially hundreds of such examples.

Second, the point I'm making is about science, not really engineering. At the engineering level, you don't need to know much about why doping a fibre with erbium works (in terms of amplifying the optical signal), to take just one example; however, to understand it from the POV of the underlying physics, you do.

Third, in terms of a scientific understanding of semi-conductor band structures or rubidium transitions, or ... you also need to have a robust, reliable view of the nature of science. As I have said, a great many times, I think such a view must give centrality to theories - in science (or at least physics) we use theories to explain, or describe, everything*. In the case of your PC+internet, the theory which underlies how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work is QED. QED incorporates SR.

Turning this around, if you claim SR to be a comprehensive failure, you have to provide a new explanation for how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work ... an explanation that does not include QED (well, you 'have to' if you are approaching this in a scientific manner).

Do you still have questions, galacsi?

Perhaps it would help if we took just one example, and showed how QED is essential for understanding how the thing works?

Or how QED so intimately depends upon (incorporates) SR?

Or how well QED stacks up against the relevant experimental and observational results?

*Within the domain physics claims to have pertinence; re your PC+internet, that certainly includes how semiconductor ICs, rubidium clocks, and optical amplifiers work.Here are your questions/assertions (the ones that are relevant):
Yeah, it relies on the QM part of QED. No one has convincingly shown that the SR part of it is also relevant. If it isn't, then "Well, they're based on QED and QED includes SR" is a fallacy of association.

"Computers" in the sense of idealized machines that carry out effective computations do not rely on any particular physical theory. However, this is irrelevant to the question at hand.No, that is precisely the question at hand.
The server on which this board runs definitely relies upon SR.How so?
Perhaps it relies on the QM part that relies on SR?And perhaps it doesn't.
And what does it have to do with SR, specifically?It seems that you are interested to understand how, in a particular, concrete example, "QM, without SR" would be different from QED?

If so, I'd be happy to provide such a specific, concrete example.

It also seems that you are confused about the initial claim, and the level at which I am answering/addressing it (the physical, nitty-gritty level; the scientific explanation). Would you be so kind as to elaborate on your confusion here?

John Mendenhall
2007-Sep-26, 03:55 PM
And what does it have to do with SR, specifically?



q.e.d. (Quod erat demonstratum.)

edit: Ah, this irritating word butchering processor spoiled my all upper case title.

peteshimmon
2007-Sep-26, 05:17 PM
My own tuppence worth. I have often wondered if
the designers of television cathode ray tubes
use some SR to get the deflection calculations
for the electron stream just right. And come
to think of it, it was cathode ray tube
experiments 100 years ago that comfirmed
SR theory I understand.

Disinfo Agent
2007-Sep-26, 06:36 PM
Disinfo Agent, did you read this post?I did. The following seems to be the only relevant part of it. The other two points are philosophy; they present no examples or evidence.


First, the main level at which relativity is important for how your PC+internet works is the physical - the nitty-gritty of band structures in the semiconductors in the motherboard chips, for example, or the atomic transition(s) that are the heart of rubidium clocks (so widely used by telecoms companies), or the optical amplifiers used for signal regeneration in fibre optics cables. Note that these are just three examples; there are, no doubt, potentially hundreds of such examples.
This, however, is quite vague. What do "the nitty-gritty of band structures in the semiconductors in the motherboard chips", "the atomic transition(s) that are the heart of rubidium clocks", or "the optical amplifiers used for signal regeneration in fibre optics cables" have to do with relativity, exactly? That isn't made clear. You've named three examples, but you haven't explained the connection between them and relativity. Which strictly relativisic effects are they based on?

I'm not saying there isn't a connection. But I can perfectly understand why Galacsi would not be satisfied with this reply. In light of this, I cannot understand the arrogance of some of the replies he got.


Here are your questions/assertions (the ones that are relevant):It seems that you are interested to understand how, in a particular, concrete example, "QM, without SR" would be different from QED?I am asking about the same thing which, as I understood him, Galacsi asked about: evidence that SR alone is necessary to explain why computers work. I already know that there are quantum effects involved. But I'd never heard that there were relativistic effects as well, which is actually very interesting. So, I think I'm very much in the same boat as Galacsi.


It also seems that you are confused about the initial claim, and the level at which I am answering/addressing it (the physical, nitty-gritty level; the scientific explanation). Would you be so kind as to elaborate on your confusion here?I hope this post has answered that. If not, please let me know.


q.e.d. (Quod erat demonstratum.)Not only are you clueless about what I'm saying, but your Latin is wrong.

galacsi
2007-Sep-26, 07:28 PM
I'm curious about what that means. I know literally, it means "you play the *** to get hay". But what is the figurative meaning? Something like "you are provoking me"?

oh Miracle ! this thread I abandoned is living its own life !

Well to answer your question : L' "âne" from latin "asinus" is better translated as "donkey".

The sentence translate : "You play the donkey to get some hay" meaning you play the stupid to make some profit .

Regards

alainprice
2007-Sep-26, 07:41 PM
Which strictly relativisic effects are they based on?


Is anything strictly relativistic?

The things themselves involve many facets of physics and therefore renders your question misleading.

Why change the question to bypass the answer?

galacsi
2007-Sep-26, 07:49 PM
AS i could not edit the above post ,even after several tries , i write a correction :

The sentence translate : "You play the donkey to get some hay" meaning you play the stupid to get some advantage or something you desire.

galacsi
2007-Sep-26, 08:00 PM
So, I think I'm very much in the same boat as Galacsi..

Thank you for your support. But i think this boat is a galley !
And we are in a very bad sargasso sea , the bad faith sea ! So the only hope is in desertion at the next port.

Nereid
2007-Sep-27, 02:30 AM
Disinfo Agent, did you read this post?I did. The following seems to be the only relevant part of it. The other two points are philosophy; they present no examples or evidence.Actually, the second and third points are integral to what I meant, way back in the post from which galacsi quoted, to start this thread.

Here they are again:
Second, the point I'm making is about science, not really engineering. At the engineering level, you don't need to know much about why doping a fibre with erbium works (in terms of amplifying the optical signal), to take just one example; however, to understand it from the POV of the underlying physics, you do.

Third, in terms of a scientific understanding of semi-conductor band structures or rubidium transitions, or ... you also need to have a robust, reliable view of the nature of science. As I have said, a great many times, I think such a view must give centrality to theories - in science (or at least physics) we use theories to explain, or describe, everything*. In the case of your PC+internet, the theory which underlies how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work is QED. QED incorporates SR.

Turning this around, if you claim SR to be a comprehensive failure, you have to provide a new explanation for how semiconductor ICs, rubidium clocks, erbium doped optical amplifiers, etc work ... an explanation that does not include QED (well, you 'have to' if you are approaching this in a scientific manner).Why are these two points important?

They go to the heart of BAUT - an internet discussion forum focussed on astronomy and space science.

If we restrict ourselves to astronomy beyond the solar system (and thus most of astrophysics and all of cosmology, as sciences), then the examples and evidence is all* just photons!

So, if you are interested in astronomy (etc) as a science, the only thing you have to account for the observations (detections of photons) are the theories.

Now of course you may live a comfortable life without ever thinking about the implications of astronomy being a science ... but then why do you hang out here?

Or, like quite a few who have started ATM threads, you may rebel against this view of astronomy as a science. Good! By all means, please present your ATM ideas, show us how you could create an SMBH in your lab (for example).

For avoidance of doubt, I'm genuinely curious to know how you can, in a logically consistent way, view astronomy as a science without having to address my third point. Would you please be so kind as to tell us?

First, the main level at which relativity is important for how your PC+internet works is the physical - the nitty-gritty of band structures in the semiconductors in the motherboard chips, for example, or the atomic transition(s) that are the heart of rubidium clocks (so widely used by telecoms companies), or the optical amplifiers used for signal regeneration in fibre optics cables. Note that these are just three examples; there are, no doubt, potentially hundreds of such examples.This, however, is quite vague. What do "the nitty-gritty of band structures in the semiconductors in the motherboard chips", "the atomic transition(s) that are the heart of rubidium clocks", or "the optical amplifiers used for signal regeneration in fibre optics cables" have to do with relativity, exactly? That isn't made clear. You've named three examples, but you haven't explained the connection between them and relativity. Which strictly relativisic effects are they based on?

I'm not saying there isn't a connection. But I can perfectly understand why Galacsi would not be satisfied with this reply. In light of this, I cannot understand the arrogance of some of the replies he got.I've started a thread (http://www.bautforum.com/general-science/65221-question-about-electrons-crts.html#post1077626), in the General Science section, on CRTs (thank you peteshimmon!). Let's see where that leads, in terms of the "strictly relativisic effects" you (and galacsi) are looking for.

Depending on the response, and interest, I'll start some more, on erbium doped optical amplifiers, band structures in the semiconductors found in computer chips, and rubidium clocks.

Thanks for making clear what, specifically, you are looking for.

Here are your questions/assertions (the ones that are relevant):It seems that you are interested to understand how, in a particular, concrete example, "QM, without SR" would be different from QED?I am asking about the same thing which, as I understood him, Galacsi asked about: evidence that SR alone is necessary to explain why computers work. I already know that there are quantum effects involved. But I'd never heard that there were relativistic effects as well, which is actually very interesting. So, I think I'm very much in the same boat as Galacsi.

[snip]This is, unfortunately, rather bound up with the "philosophy" of my third point, which you dismissed.

First, though, my original statement was not, pace you, "that SR alone is necessary to explain why computers work". That is patently absurd - SR alone says nothing about semiconductors, optical fibres, clocks, or even copper conductors, to give just a few examples.

Second, about "quantum effects": if I may quote from this wikipedia page (http://en.wikipedia.org/wiki/Quantum_electrodynamics):
Modern quantum mechanics was born in 1925 with Werner Heisenberg's matrix mechanics and Erwin Schrödinger's wave mechanics and the Schrödinger equation, which was a non-relativistic generalization of de Broglie's(1925) relativistic approach. Schrödinger subsequently showed that these two approaches were equivalent. In 1927, Heisenberg formulated his uncertainty principle, and the Copenhagen interpretation of quantum mechanics began to take shape. Around this time, Paul Dirac, in work culminating in his 1930 monograph finally joined quantum mechanics and special relativity, pioneered the use of operator theory, and devised the bra-ket notation widely used since. In 1932, John von Neumann formulated the rigorous mathematical basis for quantum mechanics as the theory of linear operators on Hilbert spaces. This and other work from the founding period remains valid and widely used.So, assuming wikipedia has its history more or less right, the quantum theory used by physicists, since the early 1930s, incorporates special relativity.

Or, to say this another way, there has been no "QM, without SR", as the theory used by working physicists, since then.

From quite a few posts in this thread, it seems this inextricable inter-twining of QM with SR was unknown to many who have posted here. If so, then I think it's worth exploring in some detail, in the General Science section.

For now though, the (crude) soundbite summary is this: all "quantum effects" in the real world involve SR, no matter what you were taught in high school, and no matter how much you'd like to deny it.

*Exceptions: an isotropic rain of cosmic rays, ~19 neutrino detections, a few nanograms of stardust, and some atoms of neutral He.

Nereid
2007-Sep-27, 01:23 PM
Thank you for your support. But i think this boat is a galley !
And we are in a very bad sargasso sea , the bad faith sea ! So the only hope is in desertion at the next port.You might be interested to read the posts in a new General Science thread that I started: In what way is it possible to have QM without (special) relativity? (http://www.bautforum.com/general-science/65238-what-way-possible-have-qm-without-special-relativity.html#post1077914)

John Mendenhall
2007-Sep-27, 05:05 PM
You might be interested to read the posts in a new General Science thread that I started: In what way is it possible to have QM without (special) relativity? (http://www.bautforum.com/general-science/65238-what-way-possible-have-qm-without-special-relativity.html#post1077914)

Quote is from Nereid's previous post, from Wiki:

"In 1932, John von Neumann formulated the rigorous mathematical basis for quantum mechanics as the theory of linear operators on Hilbert spaces."

For the posters who feel there is no connection to SR, I don't feel like spoon feeding today. Look up Neumann's math, it's also on Wiki. It certainly fulfills one's expectations for SR and GR; it is very counter intuitive.

Nereid
2007-Sep-27, 05:41 PM
Quote is from Nereid's previous post, from Wiki:

"In 1932, John von Neumann formulated the rigorous mathematical basis for quantum mechanics as the theory of linear operators on Hilbert spaces."

For the posters who feel there is no connection to SR, I don't feel like spoon feeding today. Look up Neumann's math, it's also on Wiki. It certainly fulfills one's expectations for SR and GR; it is very counter intuitive.For those interested in the math, Eric Weisstein's World of Physics can be a good resource; here's their entry on Quantum Electrodynamics (http://scienceworld.wolfram.com/physics/QuantumElectrodynamics.html) (with a list of lots of books too).

Disinfo Agent
2007-Sep-27, 07:42 PM
SR alone says nothing about semiconductors, optical fibres, clocks, or even copper conductors, to give just a few examples.Yes, I think that was what Galacsi was trying to say all along.

Kwalish Kid
2007-Sep-27, 07:53 PM
Yes, I think that was what Galacsi was trying to say all along.
Then his point was pretty useless. Just because SR is not the only theory required to explain these items does not mean that they do not rely on the theory!

Disinfo Agent
2007-Sep-28, 01:50 PM
Just because SR is not the only theory required to explain these items does not mean that they do not rely on the theory!It seems that SR isn't required at all to explain them. In which case they do not constitute evidence in favour of SR.

QED and SR are certainly related, but they aren't the same thing.

Nereid
2007-Sep-28, 02:12 PM
Just because SR is not the only theory required to explain these items does not mean that they do not rely on the theory!It seems that SR isn't required at all to explain them. In which case they do not constitute evidence in favour of SR.

QED and SR are certainly related, but they aren't the same thing.Earlier, you wrote:

SR alone says nothing about semiconductors, optical fibres, clocks, or even copper conductors, to give just a few examples.Yes, I think that was what Galacsi was trying to say all along.I'm having a tough time trying to work out what the question actually is!

Some time ago, in this thread, I wrote:
In a single line* sentence: a satisfactory, quantitative, scientific explanation of why your PC+internet works the way it does requires a theory called QED, which theory incorporates SR; remove SR and you can no longer explain how your PC+internet works.Accepting the constraints of a single, one-line sentence, I am struggling to work out what part of it you have not yet understood, DA*.

Would you be kind enough to clarify?

Specifically, what part(s) of this one-liner do you not understand? What part(s) do you think have been inadequately addressed?

*Caveat: you earlier dismissed a central part of my point, which I summarised as a core aspect of science (physics). If that is the sole reason for your rejection of my point, would you please say so, unambiguously (again)? Such a rejection would, likely, open a different exploration, close to the raison d'etre of the science-based parts of BAUT.

parejkoj
2007-Sep-28, 02:15 PM
It seems that SR isn't required at all to explain them. In which case they do not constitute evidence in favour of SR.


Since SR is an integral part of both modern quantum mechanics and modern Electrodynamics (which combined with some other stuff, make up QED), it is required to explain them within the current paradigm of physics. One could conceivably come up with a completely different physical theory which does not use SR at all, and also explains how all the things mentioned in this thread work. That would be very hard to do, and so far no one has done such a thing.



QED and SR are certainly related, but they aren't the same thing.

SR is a subset of QED.

galacsi
2007-Sep-28, 02:52 PM
Actually, it is a demonstration of both. What we think of as ordinary chemistry (and cooking, if you really want to irritate chemists, just remind them that most chemistry is a kind of cooking) actually involves minute transformations of the E=Mc^2 variety, although in the atomic shells, not in the nucleus. As I recall, Asimov discusses this in one of his books.

But it is also a demonstration of the power of black magic and prayer . Because just before my cooking I am used to invoke some devils and then for equilibrium do some prayer.And i must say that until now it has been very efficient.

I wonder also if the fact that i can cook a soup is not also a very good indication the phlogisticon theory has some merits ?

John Mendenhall
2007-Sep-28, 05:00 PM
Because just before my cooking I am used to invoke some devils and then for equilibrium do some prayer.



Yes, I knew a lady that cooked the same way, and she was very good at it.

Disinfo Agent
2007-Sep-28, 06:02 PM
SR is a subset of QED.But is it the subset that matters to computers? Nereid just said above that it isn't. Galacsi seemed to be saying the same from the start. That was his whole point, as far as I could see.

So how, exactly, does Nereid manage to convince herself that she's right and Galacsi is wrong, when the two of them have said the same? I don't get it.

galacsi
2007-Sep-28, 08:28 PM
Yes, I knew a lady that cooked the same way, and she was very good at it.

Wow , really , you did knew a lady , hey man that's great !

Nereid
2007-Sep-29, 01:14 AM
But is it the subset that matters to computers? Nereid just said above that it isn't. Galacsi seemed to be saying the same from the start. That was his whole point, as far as I could see.

So how, exactly, does Nereid manage to convince herself that she's right and Galacsi is wrong, when the two of them have said the same? I don't get it.At least twice now I have posted this:
In a single line* sentence: a satisfactory, quantitative, scientific explanation of why your PC+internet works the way it does requires a theory called QED, which theory incorporates SR; remove SR and you can no longer explain how your PC+internet works.Within the limits of a one-liner, what leads you to think this is the same as what galacsi wrote? (And where did galacsi write something very similar?)

Disinfo Agent
2007-Sep-29, 03:15 PM
That seems inconsistent with something you wrote elsewhere:


SR alone says nothing about semiconductors, optical fibres, clocks, or even copper conductors, to give just a few examples.Which is it?

Nereid
2007-Sep-29, 11:32 PM
Perhaps an example, to illustrate 'necessary, but not sufficient'.

Flour may be necessary to make bread (without flour, one cannot make bread), but it is not sufficient (you can't make bread with flour alone).

The theory called special relativity (SR) is necessary in order to explain, in a scientific sense, how your PC+internet work, but it is not sufficient (you also need, for example, a scientific theory that covers the behaviour of doped silicon).

Or, SR alone cannot explain how your PC+internet works.

Disinfo Agent
2007-Sep-30, 08:11 PM
The theory called special relativity (SR) is necessary in order to explain, in a scientific sense, how your PC+internet work, but it is not sufficient (you also need, for example, a scientific theory that covers the behaviour of doped silicon).What makes it necessary?

Nereid
2007-Oct-01, 12:04 AM
The theory called special relativity (SR) is necessary in order to explain, in a scientific sense, how your PC+internet work, but it is not sufficient (you also need, for example, a scientific theory that covers the behaviour of doped silicon).What makes it necessary?The success of QED; the fact that the electrons in PC monitor CRTs reach relativistic speeds; rubidium clocks relying upon a (Rb) hyperfine transition; specific Er-doped optical amplifier wavelengths; band structures of (doped) Si semiconductors; and so on (it would be, if written out in full, a very long list).

galacsi
2007-Oct-01, 07:12 PM
The success of QED; the fact that the electrons in PC monitor CRTs reach relativistic speeds; rubidium clocks relying upon a (Rb) hyperfine transition; specific Er-doped optical amplifier wavelengths; band structures of (doped) Si semiconductors; and so on (it would be, if written out in full, a very long list).

Yes Nereid , it is true electrons sent by an electron gun on the phosphors of a computer or of a TV monitor , reach a good fraction of c .But how this fact does demonstrate the validity of special relativity ?

Nereid
2007-Oct-01, 07:40 PM
Yes Nereid , it is true electrons sent by an electron gun on the phosphors of a computer or of a TV monitor , reach a good fraction of c .But how this fact does demonstrate the validity of special relativity ?At one level, it doesn't.

But please keep in mind the whole context of the point I made (from which you quoted, in the OP): a scientific explanation of why your PC+internet works as it does requires SR ... and (please don't leave this 'and' out) ... if you claim SR to be a comprehensive failure, you no longer have such a scientific explanation.

At another level a modern CRT computer monitor does demonstrate the explanatory power of SR ... if only because a scientific explanation of why that monitor works the way it does is not possible without SR*.

*Of course you could re-write SR in such a way that it seems quite unlike SR; this is just one example of the t's to be crossed and i's to be dotted if you wanted to nail down my point rigorously.

mugaliens
2007-Oct-02, 01:31 PM
Yes Nereid , it is true electrons sent by an electron gun on the phosphors of a computer or of a TV monitor , reach a good fraction of c .But how this fact does demonstrate the validity of special relativity ?

Because relativistic effects cause the electrons not to impact the screen where they would if only newtonian mechanics were involved. This has to be accounted and adjusted for when designing the gun.

Disinfo Agent
2007-Oct-02, 09:40 PM
Now, that looks like an answer...

Nereid
2007-Oct-03, 01:05 PM
Because relativistic effects cause the electrons not to impact the screen where they would if only newtonian mechanics were involved. This has to be accounted and adjusted for when designing the gun.Indeed.

And the relationship between the brightness of the screen and the 'gun settings' (if the electrons' (your frame) masses were unchanged by their speeds, they'd impart less energy to the phosphors, making the screen appear dimmer), the power requirements of the monitor (less power needed for electrons which behaved 'Newtonian-ly' than 'SR-ly'), the amount of lead (Pb) to put into the glass (same idea), etc, etc, etc.

Note that similar kinds of statements could be made regarding Rb clocks (the resonant frequency would be different if there were no SR, for example), Er-doped optical amplifiers (at least the exact properties of the materials required to maximise performance would be different; maybe the amplifiers wouldn't work at all?), and so on.

galacsi
2007-Oct-03, 08:43 PM
Indeed.

And the relationship between the brightness of the screen and the 'gun settings' (if the electrons' (your frame) masses were unchanged by their speeds, they'd impart less energy to the phosphors, making the screen appear dimmer), the power requirements of the monitor (less power needed for electrons which behaved 'Newtonian-ly' than 'SR-ly'), the amount of lead (Pb) to put into the glass (same idea), etc, etc, etc.

At first i thought it was convincing but now I am not so sure.Let be clear I don't deny there are some relativist effects ,but are they significant and can they be used as a proof of SR ?

Because even if the apparent mass of the electron increase as its speed begin to near c , and its speed is less than with the newtonian mechanic , its total energy is the same ; and due only to the acceleration by the electric field in the cannon gun.

So the effect on the phosphor must be the same.

And when you try to deflect the electron emitted by the cannon gun , the particle has more apparent mass but is less fast so may be you will have the same result.

What do you think ?