Room for Manas Dogra and abhas_RewCie

« first day (6 days earlier) ← previous day last day (15 days later) »

Manas Dogra

4:12 PM

@abhas_RewCie Are you aware of proofs of invariance of spacetime interval without using lorentz transformations?

abhas_RewCie

4:25 PM

@ManasDogra Lorentz Transformations are assumptions required for inveriance proof.

I guess, but a hardcore mathematician may do it.. I don't know

But what's the question?

Manas Dogra

Actually,I asked you because you are a Landau Lifshitz lover,and that is the only book I came across which proves invariance of interval without using Lorentz transformations directly...

But,the things were a bit heuristical there,so I thought if there is a more rigorous proof of that,which u have seen..just as u said "I guess, but a hardcore mathematician may do it.. I don't know.."

abhas_RewCie

@ManasDogra Ah, okay, they change notations, I mean, they do it with a different assumptions.... The most rigorous proof for it will require LIV, in short

@ManasDogra There's a geometrical one, will that work?

that doesn't uses LIV

Manas Dogra

I know that.. -_-

Everyone knows that

abhas_RewCie

@ManasDogra I don't know any non geomtrical proof for that which doesn't uses Lorentz Invariance

Manas Dogra

I have seen one group theoretical proof,which gives the "form" of it...I mean it gives Lorentz Transformations along with a constant in it,but no clue that the constant is c.

But again,it assumes,Lorentz transformations form a group..

It would be so nice,to derive it from more minimum assumptions...Geometrical proofs are the best though.

abhas_RewCie

4:35 PM

I agree, there's one way which does it by assuming whatever assumption is in the form $1 + O(t)$ then does it, but that's still using LIV, without it's form

Best way is to draw spacetime diagram and do it.

Well, LIV isn't a true law, there are physical phenomena where it deviates

Manas Dogra

@abhas_RewCie Lie group things...They claim they can derive Schrodinger's equation this way too :P .

abhas_RewCie

@ManasDogra No, nothing can derive SCH Equations, Also, you can't even verify it with GR assumptions, I think you messed up a bit

Manas Dogra

I know that....I also believe Schrodinger's equation can't be derived...it can only be "justified".

But you know,the wiki page says "Derivation",which really makes me upset whenever I see it,and they give reference to Sakurai for it... :(

Its just a trick though,they assume unitarity of time evolution operator and "derive" it.

Most people,thinks it is a true "derivation".

abhas_RewCie

@ManasDogra no, if you derive it with unitary operators, then you can't derive unitary operator. See Shankar.

Manas Dogra

4:51 PM

yes it's cyclic reasoning,and that's why i put quotes in "derive" and said that i am upset to see the word derivation..

Four years back I was delighted to see that finally some "derivation" of SE.But then... :( no true "derivation" atlast :(

abhas_RewCie

@ManasDogra no, unitary operator can be verified practically. It's easy, Stern Galachman experiment

Manas Dogra

@abhas_RewCie kabhi toh yes bolo yaar?

abhas_RewCie

@ManasDogra yes, it can be verified.

Manas Dogra

@abhas_RewCie experimentally verified,not theoretically derived :/

abhas_RewCie

yep

Manas Dogra

4:54 PM