What is the Universe expanding into..

Do you think there was anything before the big bang?

  • I don't think there was anything before the Big Bang

    Votes: 56 12.5%
  • I think something existed before the Big Bang

    Votes: 200 44.7%
  • I don't think the big bang happened

    Votes: 54 12.1%
  • I think the universe is part of a mutiverse

    Votes: 201 45.0%

  • Total voters
    447
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Mind you that original statement was general

…a magnetic field is just a Lorentz-transformed electric field…

Amazingly you supported that statement

I'm just a dumb chemist and we had to derive this.

Grammatically fine, syntax fine, physically incorrect, so I must conclude that both committed the same mistake or someone is bluffing.

Stick in the retarded potentials and the magnetic field comes flopping out. It's a standard derivation.

Working with retarded potentials it is mathematically a bit hard, even worse, statistically you almost never write an equation, and then we must accept your statement as a gospel, so let me write again Lorentz-transformed fields

E’ = E

B’ = B

E’ = γ [E + (1/c) v x B]

B’ = γ [B – (1/c) v x E]

Where
γ = 1/ √(1 – v²/c²)

It results quite obvious that you can find cases with B = 0 or B' = 0, but mind you that they are particular cases, and don't change anything, original statement is still wrong.


What gets lay people confused is that, when dealing with relativistic physics, scientists like to use normalized units where c = 1

University had a subscription to Annalen der Physik and I could read the 1905 original article and I can assure you that Einstein wrote just c, modern theoreticians…🙄

Please, stop to say "lay people" it sounds to me pejorative, all of us we are ignorant in some degree.
 
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Arrgggh! I'm exposed! 😡

Although, to be honest, I'd been hard pressed to acknowledge that I 'learned' that c is time (expressed in seconds - I guess, now I'm not sure of anything anymore) and not, what I have always thought, a speed expressed in distance/time.
Maybe I am in the wrong universe.

Jan
 
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@popilin

You mentioned the Casimir effect a while back, yes it has been experimentally verified but I thought it was due to quantum fields. I'm not sure everyone's idea of there being "something" in a vacuum includes all fields. Any vacuum we create on earth will have local fields due to terrestrial communications, the earth's magnetic/electric field, etc.

Even more interesting in the current context are the slow light experiments, with Bose-Einstein condensates and other things. No gravitational lensing necessary to observe light traveling at a tiny fraction of c.
 
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Hey not all of us are smart enough to teach how to make volcanos out of vinegar and baking soda.

Child's play, This is what we got...

How to Make a Fire Volcano (Mr. Wizard) - YouTube


Me, I asked my father to bring a can of powdered aluminum from the lab to mix with my polishing rouge. Some magnesium shavings helped to start the fun. I still wonder how I figured this stuff out at 15 without the web.
 
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Aluminum powder is pretty spectacular. Did you dad make etcha-sketches? 🙂

No just had a large well equiped lab supply, he actually analyzed pelletized ore mixes for HUGE castings like big Alice. I got to see it once, casting sand pits the size of basketball courts and the massive crucibles the size of a house, this American industry is gone.

Big Allis - Wikipedia, the free encyclopedia
 
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