Is there the possibility of absolute time

[hartlw]

Where does mass appear in Maxwells equations?

 

[Mentz114]

Hartlw:

Let's assume that a pulse of light is created when an electron jumps from one energy level to another, and it does so with spherical symmetry, and no longer influences the light wave once the process is complete. Then we could have a spherical light wave with an identifiable center.

I have to split hairs and point out this can't happen. When an electron emits a photon as a result of dropping to a lower energy level in an atom, it is emphatically not a spherical wave. Einstein describes it as a 'needle ray' in his (amazing) 1916 paper.
Momentum is exchanged between the emitted/absorbed quantum. This is the basis of laser cooling of atoms/ions.

I don't know if this affects the point you are trying to make about absolute time.

The idea of absolute time doesn't make a lot of sense when you consider that the only 'time' we know is what is measured on clocks. So there would have to an 'absolute clock' to measure 'absolute time'.

 

[hartlw]

I have a little problem with Mentz14 reply. If the photon is considered a single "particle", how can it be distributed around the source of light?. If it is a series of "particles" uniformly distributed around the source of light, what happens to the density of the photon around the circumfence of the "wave?". As the photons get further out does the distance between them decrease, or do they spread out so that the photon becomes wider and wider but the number remains the same? I would assume they would get wider, else the light "wave" might miss some objects altogether.

 

[hartlw]

How about, if light is concentrated in one direction you get a photon? So if you have a spherical wave of light, wrap it around to a single direction and you get a photon.

A spherical wave of light is a photon uniformly distributed spherically.

 

[hartlw]

Or maybe a single atom doesn't emit a spherical wave. That always bothered me, it would mean the "mass" of the electron is uniformly distributed around it's orbit and its only energy could come from "pulsating.". So it emits a photon in the direction determined by where it starts its jump. The light from a "particle," considered as a collection of atoms, would look like rays, as mentz14 reported about Einsteins article.

The only problem I have with this is the space between photons as distances get large. But the atoms in the particle continuosly and randomly emitting in different directions would address this. You wuld wind up with an average, continuos, weakening density of photons as the light expanded.

 

[Mentz114]

Hartlw:
There is no spherical wave solution of Maxwell's equations.

This is wildly off-topic, and I don't want to get into another discussion about photons.

see https://www.physicsforums.com/showthread.php?t=270084

 

[hartlw]

Newtonian mechanics identifies an approximate, absolute, inertial reference frame wrt distant stars. By extension, and for practical purposes, any frame moving at constant velocity with respect to this "absolute" inertial frame can be considerded an inertial reference frame.

I am off topic with photons, but I appreciate mentz114 bringing it up, since it has led to the resolution of the wave/particle duality paradox: there isn't any. I feel quite comfortable with them now, making any further discussion unnecessary. Thanks again mentz114, seriously. I appreciate expertise.

 

[Dale]

Newtonian mechanics identifies an approximate, absolute, inertial reference frame wrt distant stars. By extension, and for practical purposes, any frame moving at constant velocity with respect to this "absolute" inertial frame can be considerded an inertial reference frame.

You sure seem to enjoy making the same mistake over, and over, and over, ...

 

[hartlw]

Dalespam,

Thanks for your opinion.

 

[atyy]

Newtonian mechanics identifies an approximate, absolute, inertial reference frame wrt distant stars.

Doesn't Newtonian mechanics identify an exact inertial frame as the centre of mass frame? Given the centre of mass frame we can identify an continuous infinity of other inertial frames. So the identification is exact within a mathematical framework that is experimentally known to be an approximate description of nature.

 

[The Dagda]

Doesn't Newtonian mechanics identify an exact inertial frame as the centre of mass frame? Given the centre of mass frame we can identify an continuous infinity of other inertial frames. So the identification is exact within a mathematical framework that is experimentally known to be an approximate description of nature.

No, it is not experimentally known to be anything that's the point, Newton was wrong as was Galileo.

 

[hartlw]

No, it is not experimentally known to be anything that's the point, Newton was wrong as was Galileo.

Now that you've tossed out Newton and Galilea, what physical law explains (actually, describes) the rotation of the Earth about its axis? I take it you accept that as physical evidence?

 

[Dmitry67]

Newtonian mechanics identifies an approximate, absolute, inertial reference frame wrt distant stars.

Taking into account the Hubble law (expansion of the universe) you can't do that: in different parts of the universe these frames are different and moving relatively to each other.

 

[Dale]

Doesn't Newtonian mechanics identify an exact inertial frame as the centre of mass frame? Given the centre of mass frame we can identify an continuous infinity of other inertial frames. So the identification is exact within a mathematical framework that is experimentally known to be an approximate description of nature.

Yes, in Newtonian mechanics the center of mass frame of an isolated system is exactly inertial as is any frame moving with a uniform velocity wrt the center of mass frame.

The rather trivial objection that hartlw was raising is that there is no such thing as a truly isolated system. The objection is trivial because, given a non-isolated system of mass M with force F acting on it, then an inertial frame is simply one where the center of mass is accelerating at a=F/M.

 

[The Dagda]

Now that you've tossed out Newton and Galilea, what physical law explains (actually, describes) the rotation of the Earth about its axis? I take it you accept that as physical evidence?

Einstein's theory of general relativity? Why?

 

[Species8472]

Is there a theory of absolute time that is compatible with General Relativity?

(This question inspired by a thread on http://www.freeratio.org/showthread.php?p=5740883#post5740883".)

Did Bob actually post here at all?

 

[hartlw]

Just notified of this in my email so I thought I'd comment.

Absolute time is ANY definition of time, ANYWHERE, and a method of synchronization.

The definition of time in Maxwell's equations and on Earth is as good as any. For a synchronization method see posts 34 & 35 in the thread

http://www.advancedphysics.org/forum/showthread.php?t=11435

where it is assumed that the speed of light in vacuum is constant wrt SOURCE.

Relativity, which is wrong, has nothing to do with it. See same thread.

 

[Dale]

Relativity, which is wrong, has nothing to do with it.

http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html