Recent content by Pavel

Hi Phrak, There's a difference between an idealized experiment, in which things are considered in principle, and an actual experiment, under certain physical conditions. When Enstein imagined what would happen if he was riding a beam of light, he was not conducting an actual experiment...

Airplane on the treadmill A friend of mine told me about this mush discussed thought experiment (http://en.wikipedia.org/wiki/Airplane_treadmill_problem ). We immediately got into a debate, but we shortly reached an agreement. I wanted to run it by somebody who understands physics and tell me...

CompuChip, thank you very much for the explanation. Loved the joke too :) Pavel

Hi, does it make sense to posit a curved (hall of mirrors type) space without higher dimensions? In other words, if I say we live in a 3 dimensional torus shaped universe, does that statement necessarily entail there's at least a 4 dimensional overall hyperspace? Or can I have a torus curved...

No, it's not a paradox. At worst, it can be argued to 'beg the question' (conclusion is presumed in the premise), or be reduced to a tautology - empirically untestable truth by definition, like "a bachelor is an unmarried man". In other words, the notion of survival can be analytically derived...

Thank you for your help. Would I be correct then to summarize what you say, in down to Earth terms, as following: The recent observations, such as done by WMAP suggest that, as far as we can see, the Universe is flat, save a few very small irregularities here and there. However, such...

I thought the curvature was really a "local" thing and had little bearing on the overall topology. IN other words, all possible three curvatures are still consistent with a torus. So, even if the CMBR shows flatness as far as we can see, the overall universe can still be toroidal. Can it not...

Hi, I've read this article (http://www.space.com/scienceastronomy/mystery_monday_040524.html), which says: "In the new study, researchers examined primordial radiation imprinted on the cosmos. Among their conclusions is that it is less likely that there is some crazy cosmic "hall of mirrors"...

Ah, that's it. Makes sense now. Thanks! Moonbear, I appreciate your help too. Pavel.

Hi, the following is from Steven Pinker's debate (against Rose). Can somebody please translate this into more understandable language. I know what allele and average and all the individual terms mean, but I just don't get the concept and I want to know what evolutionists mean when they say "a...

I see. Well, you really answered my question to the level of detail I needed. Thank you for doing that. Pavel.

Ah, my apology. I did misunderstand your point. This would be more of a reductio ad absurdum "proof" for the infinite universe, rather than direct evidence. Thanks for the insight.

Jesse, I'm afraid you're talking about unbounded, but finite universe (like the surface of a sphere). They're talking about infinite universe. Alexander Vilenski, for example, believes: There are good reasons to believe that the universe is infinite. If so, it contains an infinite...

I was reading the answers by some scientists (including Krauss) to the question "What do you believe but cannot prove" on edge.org, who say there are good reasons to believe the Universe is infinite. They don't mention what those reasons are, but I was wondering if somebody could comment on...

I ran across this interesting "friendly" exchange between these two titans of modern biology arguing over whether the natural selection happens WITHIN the species (Dawkins) or among groups (Dyson). I'm in no position to be the arbitrator, but I would love to hear some opinions from the people...