Ask a physicist anything. (8)

[razeontherock]

You sure there isn't a subliminal message hidden in there somewhere?

 

[Wiccan_Child]

So what we can know has hard limits? Ok ...

Absolutely. Quantum Mechanics has the Uncertainty Principles, which place hard limits not just on how accurately we can know something's position and momentum, but on how 'discrete' its momentum actually is.

Some mathematical problems don't have a solution - we can prove that there simply isn't any way to do the algebra and pop out a solution, for the general case. Usually, for a specific case, the mathematics is just long-winded. It can be done, but only when you plug in specific variables.

 

[Naraoia]

That tachyon issue... is... actually... really weird if you think about it.

I mean, for an ordinary particle, the range of possible speeds has a well-defined lower end: zero. In the name of symmetry, is there a fastest speed tachyons can theoretically move at? A sort of equivalent to speed zero mirrored on the other side of light speed?

 

[AV1611VET]

Does England have an equivalence of NASCAR?

 

[mzungu]

Does England have an equivalence of NASCAR?

And your point being

 

[Wiccan_Child]

Does England have an equivalence of NASCAR?

Top Gear

 

[Nabobalis]

Does England have an equivalence of NASCAR?

Closest would be British Touring Car Championship. But we happen to drive on real tracks.

 

[Zippy the Wonderslug]

Hey all.

Starting my car has been a little goosey as of late.

I think it's just my ignition switch.

Anyway, I'm fearful of turning off the engine since there are times when I can't start it again.

What is the worst thing that could happen, filling the gas tank up, while the car is still running?

I've got a friend who will fix this for me, but not for another week.

I don't want to abandon my car at a gas station if I'm unable to start it again and I also don't want to suffer a horrible, searing, death by fire and explosions as well.

Many cheers ahead for any answers on this.

 

[NGC 6712]

Does England have an equivalence of NASCAR?

Non Athletic Sport Centered Around Rednecks.

 

[Feileacan]

Have you considered this?

Physics doesn't exist, it's all about Gnomes - Uncyclopedia, the content-free encyclopedia

 

[Zippy the Wonderslug]

Aww... I wish someone would post an answer to my last question but it doesn't look like this is going to happen...

Oh well.

Anyway, what are the possible chances in this world that a space elevator will ever be made?

Instead of always flying there, we build a stupid and excessively tall building and just press a fun button so we can view and send crap in and out of space without the need for lift off from an expensive spaceship each time.

As always....

Thanks ahead for any responses.

 

[mzungu]

Aww... I wish someone would post an answer to my last question but it doesn't look like this is going to happen...

Oh well.

Anyway, what are the possible chances in this world that a space elevator will ever be made?

The only material light enough and strong enough to take the stresses involved that will allow us to actually build a space elevator are carbon nano tubes. Here is an interesting link: Long, Stretchy Carbon Nanotubes Could Make Space Elevators Possible

 

[Non sequitur]

W_C, or whomever, what are your thoughts on Lawrence Krauss and his "A Universe from Nothing" (and the thoughts/material in it; open/flat universe, etc.)?

 

[Wiccan_Child]

W_C, or whomever, what are your thoughts on Lawrence Krauss and his "A Universe from Nothing" (and the thoughts/material in it; open/flat universe, etc.)?

I haven't read it, so I can't comment. I've heard good things, though. What's the general gist?

 

[Non sequitur]

I haven't read it, so I can't comment. I've heard good things, though. What's the general gist?

I wouldn't even try to attempt, that's why I asked

Try here or SOMETHING FROM NOTHING ? [OFFICIAL] Richard Dawkins & Lawrence Krauss [HD] 02-04-12 - YouTube to get a gist of it, in video format.

WARNING: Some material may be offensive to humans.

 

[Naraoia]

I have to say Lawrence Krauss is effin' hilarious.

 

[Michael]

I haven't read it, so I can't comment. I've heard good things, though. What's the general gist?

I can't say much about Dawkings because I haven't sat through the second video yet, but Lawrences concept of something for nothing is based on the premise the the force of gravity somehow offsets the rest of the kinetic energy of the universe. His whole "flat universe" concept is a "necessary" requirement for his belief system to have merit (apparently). Never mind the fact that all energy is kinetic in nature and not all of it has rest mass. His theories are nothing short of a major violation of the laws of thermodynamics. There is no such thing as a cosmic "free lunch". It's another atheistic meme, nothing more.

 

[Wiccan_Child]

His theories are nothing short of a major violation of the laws of thermodynamics.

So?

 

[Michael]

I wouldn't even try to attempt, that's why I asked

Try here or SOMETHING FROM NOTHING ? [OFFICIAL] Richard Dawkins & Lawrence Krauss [HD] 02-04-12 - YouTube to get a gist of it, in video format.

WARNING: Some material may be offensive to humans.

Gah, I couldn't get very far into the second video the first time through before becoming thoroughly amused/disgusted. It took me a few tries to get through the first video a few months back. I love the part in the second video where they sit there and complain about a "God of the gaps" argument in relationship to evolutionary theory while Krauss is one of the biggest promoters of a "dark energy/dark matter/magic inflation" of the gaps argument. Every argument they used could as easily apply to any of the three metaphysical gap fillers of astronomy theory. The whole thing comes off as rather ironic from my perspective. The part of the discussion about evolutionary theory got off to a bad start IMO. Dawkins seemed to at least understand he HAS gaps issue to deal with in terms of where DNA comes from, but he doesn't seem to understand the concept of a creator/universe that constantly 'plays' in it's creation. Krauss IMO is just another clueless militant (fundy) atheist. That whole 'at least I know Dawkins is real' in relationship to Moses shows how far he takes his fundy beliefs IMO.

Maybe I'll try the video another time when it's not quite so busy at work.

 

[Michael]

So?

So generally I don't personally put a lot of value in theories that violate the laws of physics. I therefore don't find his ideas to be particularly compelling. I'm not even sure why he finds a flat universe compelling evidence to support his current beliefs since Penrose demonstrated that a flat universe is MUCH more likely to occur in the ABSENCE of inflation, something like 10 to the 100th power more likely in fact.

Inflation (cosmology) - Wikipedia, the free encyclopedia

IMO Krauss comes off looking a rather hypocritical all things considered.

FYI, his ideas also ignore the concept of USE OF ENERGY OVER TIME. In other words to 'balance out' the overall energy via gravity, you have to IGNORE the fact it's in use, and changing forms forever and ever.