inside Einstein's head

[gib65]

In researching the beginnings of quantum theory, I think I found a connection between Plank’s energy quantization hypothesis and Einstein’s theory of special relativity. It seems as though Einstein was so taken by Plank’s theory, that a whole flurry of insights were spawned in his head and subsequently published – all in 1905. Starting with the concept of energy packets that Plank proposed only as a mathematical formality, Einstein resurrected the corpuscular theory of light, and then went on to explain the photoelectric effect. Special relativity was published in the same year, which leads me to believe it was inspired by the same source – Plank’s energy quantization.

 

If I could get inside Einstein head, I think I would find these thoughts:

 

“Hmm… Light is corpuscular, after all. Well, that does away with the ether. As a wave, light would need a medium like the ether, but as a stream of particles… That puts that problem to rest, except for the Michelson-Morley experiment, and the implication that falls out of it – namely, that the speed of light is absolute. That is a quandary… but without the ether, it might work… so long as…” and the rest is history.

 

Maybe this is no secret. Maybe it’s common knowledge among physicists how Einstein’s train of thought linked Plank’s energy quantization to special relativity. But it isn’t to me, so I’m putting this out there for others to either confirm or show me how far out to lunch I am. Any thoughts?

[swansont]

Constant c is a consequence of Maxwell's equations that took on new meaning when it was realized that light was an electromagnetic wave. Also, Lorentz had already published the transformation equations and IIRC Einstein had stated that he was unaware of the Michelson-Morley experimental results when he published.

[pioneer]

I am not sure if this was Einstein's train of thought but here goes. We know E=MC2. We also know kinetic energy is E=1/2MV2. As the kinetic energy increases, since the mass has an equivilency to energy, than the mass must increase because of the velocity due to the kinetic energy. But where does that get me? Wait a minute, the total energy of my system was the energy in the orginal mass, plus the mass that I gained due to the kinetic energy. Now we are starting to get somewhere.

 

OK, the kinetic energy E will increase my mass= Ek/C2. I need to add this to my original mass, and then recalculate the kinetic energy, since the very motion will add energy to my mass which is also equivilent to mass. Come on Al, you are almost there. "Could someone get the cat?". Where was I? OK, lets try this again.....These two basic relationships were all he needed. The creative process was Einstein giving birth to relativity.

[swansont]

I am not sure if this was Einstein's train of thought but here goes. We know E=MC2. We also know kinetic energy is E=1/2MV2. As the kinetic energy increases, since the mass has an equivilency to energy, than the mass must increase because of the velocity due to the kinetic energy. But where does that get me? Wait a minute, the total energy of my system was the energy in the orginal mass, plus the mass that I gained due to the kinetic energy. Now we are starting to get somewhere.

 

OK, the kinetic energy E will increase my mass= Ek/C2. I need to add this to my original mass, and then recalculate the kinetic energy, since the very motion will add energy to my mass which is also equivilent to mass. Come on Al, you are almost there. "Could someone get the cat?". Where was I? OK, lets try this again.....These two basic relationships were all he needed. The creative process was Einstein giving birth to relativity.

 

The (relativistic mass energy -rest mass energy) relation will reduce to 1/2 mv² for small v. Using the latter equation, you don't both increase the mass and v; you would use the invariant mass. You don't get to mix and match — you have to be consistent or you will end up with nonsense.

[gib65]

Constant c is a consequence of Maxwell's equations that took on new meaning when it was realized that light was an electromagnetic wave.

 

But they didn't know, at that time, that the speed of light was absolute, did they?

 

IIRC Einstein had stated that he was unaware of the Michelson-Morley experimental results when he published.

 

You may be right, but Prof. Richard Wolfson of Middlebury College says that it is unknown whether Einstein knew about the Michelson-Morly experiment or not.

[swansont]

But they didn't know, at that time, that the speed of light was absolute, did they?

 

It was for electromagnetic systems. The wave equation would fail otherwise. What Einstein did was apply this concept to mechanical systems, i.e. objects with (rest) mass.

 

 

 

You may be right, but Prof. Richard Wolfson of Middlebury College says that it is unknown whether Einstein knew about the Michelson-Morly experiment or not.

 

Eistein said he didn't, or at least was only vaguely familiar with it, and it wasn't a driving force behind his theory. As he was was cut off from scientific inquiry — i.e. a patent clerk, not in academia at the time — it's certainly plausible.

 

http://www.time.com/time/magazine/article/0,9171,878733,00.html

http://www.scientificblogging.com/nithyanand_rao/what_i_never_realized_about_relativity

http://www.physics.ucla.edu/demoweb/demomanual/modern_physics/special_relativity/special_relativity.html

[lucaspa]

Special relativity was published in the same year, which leads me to believe it was inspired by the same source – Plank’s energy quantization.

 

This is the premise: because 2 papers were published in the same year, they were inspired by a common source.

 

Is this mandatory? Einstein was working on several different problems in his head at the same time. Most scientists do. This doesn't mean that they were related.

 

Look, you can try to guess what Einstein was thinking all you want. IMO, it's a pretty pointless exercise unless and until you can find Einstein telling you what he was thinking. Do you have that? Do you have any writing BY Einstein telling you his thought processes when he wrote those 3 seminal papers?

 

As it turns out, there isn't an obvious link between gravity -- the subject of Special Relativity -- and quantum mechanics. And QM is an outgrowth of Planck's quantization. IF there were a connection, then why did Einstein futilely spend the last 50 years of his life trying to unify SR and QM?

[gib65]

It was for electromagnetic systems. The wave equation would fail otherwise.

 

But this could work in an ether at absolute rest as well, couldn't it? Otherwise, I can't imagine why Michelson and Morly would have bothered with their experiment, expecting different time delays for their light beams to complete their journey.

 

This is the premise: because 2 papers were published in the same year, they were inspired by a common source.

 

This is not a logical deduction, it's just I guess that I feel confident about. Why else would I have put it under "speculation"?

 

IMO' date=' it's a pretty pointless exercise

[/quote']

 

No one's forcing you to do it.

 

gravity -- the subject of Special Relativity -- and quantum mechanics.

 

Uh... gravity is not the subject of SR - you're thinking of GR.

 

IF there were a connection' date=' then why did Einstein futilely spend the last 50 years of his life trying to unify SR and QM?[/quote']

 

I didn't say there was a connection. I just suggested that Plank's hypothesis of energy quantization resurrected a corpuscular image of light, and with that the implication that there was no need for the ether, and with that the implications of time dilation at high velocities etc.

[swansont]

But this could work in an ether at absolute rest as well, couldn't it? Otherwise, I can't imagine why Michelson and Morly would have bothered with their experiment, expecting different time delays for their light beams to complete their journey.

 

Yes, M&M were trying to do an ether measurement, but it was to measure our speed with respect to the ether. The observation of stellar aberration (Bradley, in 1727) had already established that we were not at rest. Einstein came at the problem from a different direction.

[lucaspa]

But this could work in an ether at absolute rest as well, couldn't it? Otherwise, I can't imagine why Michelson and Morly would have bothered with their experiment, expecting different time delays for their light beams to complete their journey.

 

It was already known that earth was moving. If the aether was a medium thru which light traveled, then earth is moving through the aether by moving in its orbit. Even if the aether is moving, that still means that earth's velocity relative to the aether would be different at if you looked in different directions. http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/mmhist.html

 

lucaspa: This is the premise: because 2 papers were published in the same year, they were inspired by a common source.

 

This is not a logical deduction, it's just I guess that I feel confident about. Why else would I have put it under "speculation"?

 

I said it was a premise. Premise and deduction are two different things. You start with a premise and make a deduction. Your "guess" is the decution from a syllogism:

Premise 1: 2 papers published in the same year mean they were inspired by a common source.

Premise 2: Einstein published 2 papers in the same year.

Deduction: Einstein's papers were inspired by a common source.

 

Syllogisms can be wrong for a number of reasons. For instance, the deduction can be a non sequitor from the premises. However, another way a syllogism can be wrong is for one of the premises to be wrong. This was what I was doing: calling into question one of the premises.

 

Uh... gravity is not the subject of SR - you're thinking of GR.

 

OK, SR is about the structure of spacetime. My comment still applies because spacetime is continuous and not quantized. Loop quantum gravity is a new theory that is trying to quantize spacetime and thus unite quantum mechanics with GR. IF SR was related to QM, Einstein could have done this a long time ago.

 

I just suggested that Plank's hypothesis of energy quantization resurrected a corpuscular image of light, and with that the implication that there was no need for the ether, and with that the implications of time dilation at high velocities etc.

 

This is a non-sequitor. Planck's equation is E = hv where v is the frequency of light. Frequency is "the number of complete oscillations per second of energy (as sound or electromagnetic radiation) in the form of waves"

 

So, Planck's work still had light traveling in waves. Planck did not displace wave theory, but implied the dual nature of light: waves and particles. Now, according to your logic, wouldn't you still need an aether for the waves to travel thru?

[gib65]

Premise 1: 2 papers published in the same year mean they were inspired by a common source.

 

I never made such a statement. I said that 2 papers published in the same year might mean they were inspired by a common source. The "might" carries through to the conclusion too: Einstein might have been inspired by Planck's quantum hypothesis. Also, "inspired" doesn't have to mean "logically deduced from" - it could just mean "made him think of".

 

So, Planck's work still had light traveling in waves. Planck did not displace wave theory, but implied the dual nature of light: waves and particles. Now, according to your logic, wouldn't you still need an aether for the waves to travel thru?

 

This is actually a good point. Planck's hypothesis doesn't resurrect the corpuscular theory of light. It should be noted however, that Einstein did point out the similarities. Planck himself only proposed his hypothesis as a mathematical formality such that the formula for the energy of black body radiation would fit the data. Einstein took the next step and proposed that light really is composed of particles (later dubbed the "photon").