Recent content by ivan

Then this must be most important thing since theories may be wrong. If I can't even in principle set up an experiment where dice throwing can be shown to be deterministic then how does it matter what I call it(deterministic randomness vs. nondeterministic randomness)? Could you translate that in...

Thank you. So then quantum randomness is nondeterministic meaning one could not predict outcome just because it is non-computable even in principle. Is this right?

quantum randomness vs. "dice randomness" Can anybody explain what's the difference between quantum randomness and "regular" randomness, please. (say random distribution of dice-faces when throwing a dice)

Thank you all. Your explanations were very clear.

Thanks. So, as I understood since 0 is a real number unary operations both + and - is defined for 0 such that +0=0 and +0+(-0)=0 (per definition of additive inverse). Since +0+(-0)=0 and +0=0 => 0+(-0)=0 => -0=0 too. Am I right?

Somebody asked me how absolute value of a real number can be defined. I said |a| is defined as +a if a>=0 and -a if a<0 (instead of, |a| is defined as a if a>=0 and -a if a<0). Then came an objection that with such a definition if a=0 its absolute value should be +0 and there's no such thing...

Thanks everybody. I think I understand it now.

Thank you for response but I can't understand still one thing. Here are two quotes from that website: Quote #1: This to me means that any given star for a given location will rise 23 hours and 56 minutes apart for each consecutive rise. This also means that for each consecutive positions of...

I'm reading Nick Strobel's astronomy notes. I should mention that it's an excellent website for an amateur like me. I can't get one thing right though. He mentions about fixed coordinates of stars measured in RA (right-ascension) and declination. He says that "Earth's rotation is broken up into...

I apologize for this question asked in this thread, but I tried to avoid opening new thread. My question relates to simultaneity in relativity. Say we have a moving frame A with regard to a rest frame B. A moves with velocity v in the B's frame. If two events in A (from the A's observer's point...

Thank you. That was a very clear explanation.

Thanks for nice words.

Hi all I was recently told that certain postulates of SR are equivalent or one can be derived from the other. Namely 1) The speed of light in vacuum is constant and is independent of the speed of emitting body; 2) The speed of light is impassable limit; I did some search and found quite...

Before I ask you next question with your permission, I want to digress from the main point for a second. You have expressed this idea before and I completely agree with you. Namely, in physical theories we have many abstract descriptions. You have mentioned one of this somewhere in quantum...

Sorry, I did not mean to insult you. What I meant was there's no objective description of time since there's no unitary idea of time in physics, or different parts of physics. I want to clarify this for me. If I'm mistaken please correct me. When we say position is an 'observable' we probably...