Ask a physicist anything. (4)

[Wiccan_Child]

This thread was split automatically after 1000 replies and this thread has been automatically created.
The old thread automatically closed is here: "Ask a physicist anything. (3)"

 

[pgp_protector]

So how do you like having a thread go on for 4 cycles now?

 

[SithDoughnut]

When do I get my hoverboard?

 

[Wiccan_Child]

So how do you like having a thread go on for 4 cycles now?

I feel like a father whose child has just turned 4! Surely we've run out of physics questions after 3000+ posts...

When do I get my hoverboard?

Fifth cycle, then hoverboards for EVERYONE

 

[SithDoughnut]

Fifth cycle, then hoverboards for EVERYONE

See, now I'm going to be forced to just spam questions until I get my hoverboard.

... Or at least I'll spam some when I think of some.

 

[KIYX]

Bravo! Great thread!

 

[PhoceanCity]

Somehow I liked the question about the quantity of water needed to put off the sun. So what would it take to stop the reaction inside a star?
And just in case, it's not me who wants to know, it's a friend... yeah, a friend...

 

[pgp_protector]

Somehow I liked the question about the quantity of water needed to put off the sun. So what would it take to stop the reaction inside a star?
And just in case, it's not me who wants to know, it's a friend... yeah, a friend...

you can probably just use some red matter made from decalithium to destroy the Sun.

 

[PhoceanCity]

you can probably just use some red matter made from decalithium to destroy the Sun.

Don't be silly, I would be stuck with a young starfleet officer and his disfonctionnal crew, they would end up beating the living hell out of me creating a time paradox and maybe a whole new serie of awesome adventures

 

[Wiccan_Child]

Somehow I liked the question about the quantity of water needed to put off the sun. So what would it take to stop the reaction inside a star?
And just in case, it's not me who wants to know, it's a friend... yeah, a friend...

You'd need to soak up all the ionised Hydrogen floating about. Or, ironically, put a load more in - the star will burn up quicker.

you can probably just use some red matter made from decalithium to destroy the Sun.

Just so long as you don't time-travel your homeworld out of existence. You'll never live that one down...

 

[PhoceanCity]

Or, ironically, put a load more in - the star will burn up quicker.

But wouldn't it make the star burn something else, like helium or iron when all the hydrogen have fused?

 

[Wiccan_Child]

But wouldn't it make the star burn something else, like helium or iron when all the hydrogen have fused?

Sure, but since the star is fundamentally made of these gases, you can't stop it burning them without dismantling the entire star. Anything you put into it will be incorporated into the fusion process.

 

[shinbits]

In the movies, mirrors can be used to deflect lasers. Now while it makes sense lasers that aren't destructive, I also see movies where lasers that are able to cut steel are deflected by mirrors. Is this actually true, or just sci-fi drivel?

 

[Wiccan_Child]

In the movies, mirrors can be used to deflect lasers. Now while it makes sense lasers that aren't destructive, I also see movies where lasers that are able to cut steel are deflected by mirrors. Is this actually true, or just sci-fi drivel?

A laser that melts through steel is unlikely to have much trouble with a mirror - steel melts about 3000°C, glass at about 200°C (off the top of my head). That said, with very precisely mirrors, you might be able to spread the laser beam lengthways, displacing much of the heat.

 

[hisgrace26]

I have 2 questions:

1. What does it mean when Physicist say "nothing"?
2. Can non-existence be defined?

From what I understand, logically speaking, "nothing" has no properties so it's nothing. For something to exist it must have attributes. What are your thoughts on this?

 

[Wiccan_Child]

I have 2 questions:

1. What does it mean when Physicist say "nothing"?

"I have nothing to do!" means that the physicist's to-do list is empty. It's kinda like that.

2. Can non-existence be defined?

If something does not exist, it is non-existent.

From what I understand, logically speaking, "nothing" has no properties so it's nothing. For something to exist it must have attributes. What are your thoughts on this?

Neither existence nor nothingness are either properties or things that can have properties, and nor does an extant thing necessarily have to have properties.

 

[Spiegelman's Monster]

How is it that astrophysicists can posit a universe where T< infinity, but where V = infinity, which is my understanding of the current view?
(T=time, V = volume)

 

[Wiccan_Child]

How is it that astrophysicists can posit a universe where T< infinity, but where V = infinity, which is my understanding of the current view?
(T=time, V = volume)

Do they? We don't know the topology of the universe (it could be a bubble of finite area, it could be infinite in all directions, it could be an open surface, etc), and we don't know how old it is either (we know it's at least 13.5 billion years old, but what, if anything, happened before then?).

 

[hisgrace26]

"I have nothing to do!" means that the physicist's to-do list is empty. It's kinda like that.


If something does not exist, it is non-existent.


Neither existence nor nothingness are either properties or things that can have properties, and nor does an extant thing necessarily have to have properties.

Thanks! Now my next question: Does gravity have mass and volume?

 

[Deleteriousnonsense]

Did you hear the one about the physicist, the engineer, and the statistician? They all went hunting and spotted a deer. The physicist calculated the distance to the dear, raised his rifle and fired, but his shot went a little long. Quickly the engineer raised his rifle, adjusted for windage, and fired. His shot fell a bit short. As the deer bounded away the statitician exclaimed, "We got him!"