Ask a physicist anything. (2)

[SithDoughnut]

You're going to need a lot of thread -- and how's a boy scout supposed to lug around one of those?

Boy Scouts are lazy. We should beef them up (get it? Beef? ) by making them carry cows around.

 

[Nathan Poe]

Boy Scouts are lazy. We should beef them up (get it? Beef? ) by making them carry cows around.

And that is why I left the scouts -- that, and I spent the time I was supposed to be getting my Astronomy Merit Badge checking out the houses down the street.

 

[Assyrian]

You're going to need a lot of thread -- and how's a boy scout supposed to lug around one of those?

Just strap a frame and some block and tackle to the back of the cow and it lugs itself around.

 

[catzrfluffy]

What happens if you wear a magnet-hat? Can you have the same ability? Is it true if you have a plate in your brain you can tune in to Radio 4?

 

[Wiccan_Child]

What happens if you wear a magnet-hat? Can you have the same ability? Is it true if you have a plate in your brain you can tune in to Radio 4?

Yes. All you need is a working radio. The plate in your brain is optional .

 

[DiabeticDude]

Is it true that all of time exists?

 

[Assyrian]

Does time exist?

 

[Wiccan_Child]

Is it true that all of time exists?

Does time exist?

According to Einsteinian Relativity, yes, it is as real as space and matter.

 

[Assyrian]

According to Einsteinian Relativity, yes, it is as real as space and matter.

If that is what Einstein says, does that mean quantum mechanics will disagree?

 

[Wiccan_Child]

If that is what Einstein says, does that mean quantum mechanics will disagree?

No, since quantum mechanics and relativity only disagree about what happens to spacetime on very small scales (e.g., they disagree on what happens to matter in the singularity of a black hole). The nature of time and space isn't really addressed by quantum mechanics, so there's not much for them to disagree on.

Relativity, as it stands today, is probably wrong. But it's right enough that we know time to exist as much as space and matter exist (much as, though classical mechanics is wrong, it's still right enough that we know billiard balls will roll in a straight line).

 

[DiabeticDude]

According to Einsteinian Relativity, yes, it is as real as space and matter.

If, therefore, all of time exists why is it now?

 

[Wiccan_Child]

If, therefore, all of time exists why is it now?

If all of space exists, why is this particle here?

 

[DiabeticDude]

If all of space exists, why is this particle here?

Slightly easier to get my head round than the fact that somewhere out there I'm dying.

 

[Wiccan_Child]

Slightly easier to get my head round than the fact that somewhere out there I'm dying.

Technically, you're dying right now. Every moment is one step closer to an inevitable death. Life is a terminal disease!

 

[Doveaman]

Relativity, as it stands today, is probably wrong.

But it's right enough that we know time to exist as much as space and matter exist (much as, though classical mechanics is wrong, it's still right enough that we know billiard balls will roll in a straight line).

 

[Assyrian]

No, since quantum mechanics and relativity only disagree about what happens to spacetime on very small scales (e.g., they disagree on what happens to matter in the singularity of a black hole). The nature of time and space isn't really addressed by quantum mechanics, so there's not much for them to disagree on.

Relativity, as it stands today, is probably wrong. But it's right enough that we know time to exist as much as space and matter exist (much as, though classical mechanics is wrong, it's still right enough that we know billiard balls will roll in a straight line).

There was an article in New Scientist a year ago (as it were) saying you could formulate quantum mechanics without reference to time, with the implication time may not exist Is time an illusion? - physics-math - 19 January 2008 - New Scientist Sounds like a fun hypothesis. I was wondering if you came across the idea.

 

[Doveaman]

If, therefore, all of time exists why is it now?

If all of space exists, why is this particle here?

I always thought "here" and "now" were two different concepts.

Is there 'herenow' in General Relativity?

 

[Wiccan_Child]

I always thought "here" and "now" were two different concepts.

Is there 'herenow' in General Relativity?

Yes, inasmuch as 'here' is a point in space, 'now' is a point in time, and 'herenow' is a point in spacetime.

 

[Wiccan_Child]

There was an article in New Scientist a year ago (as it were) saying you could formulate quantum mechanics without reference to time, with the implication time may not exist Is time an illusion? - physics-math - 19 January 2008 - New Scientist Sounds like a fun hypothesis. I was wondering if you came across the idea.

I think that's just journalists getting away with themselves. As good as New Scientists is, it still needs to make a profit...

 

[TerranceL]

Dear Science Person,

Is this cool?

http://www.youtube.com/watch?v=SAnDeh9xNHU