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Time Travel (pg. 5)
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| DJ Mikey Mike |
| quote: | Originally posted by djSlain
how come if:
you have a flashlight
a metal box with a removable top
u flash the light into the box, then suddenly you close the box and seal it.
is there still light inside the box and once u open it the light escapes and whatever. .
i have weird questions eh? |
the light escapes faster than u can close the lid :p u cant trap light. |
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| djSlain |
| how about just leaving the flashlight on in the box and waiting for the battery to run out. when the battery dies, is light still bouncing around in there or something? |
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| King_Mack |
| sure but for a short period of time. Light can go through walls(quantum tunneling) so I dont know how much good that would be. But what would be the point of that? are you trying to study light trapped within a container or something? |
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| djSlain |
| it's just that this has been one of the better threads in chill out ream. i have so many questions and i think it's very interesting |
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| dj2kTA |
| quote: | Originally posted by Dumonde Trancer
i am more interested on any further developements of this story!
come on, wether you belive in time travel or not, id liek to see how he could make all that money on jsut "inside information" alone. |
Its easy if he has information about a company's 'secret' research and developments, etc.
For example, if a drug company is researching a new drug that is supposed to cure AIDS, and this dude knows about it before it becomes public information he can buy the company's stock. When the information becomes public you can be for sure that the said company's stock price will skyrocket. Thats because when the drug is marketed and sold, the company will have sales and profits coming out their asses. Hence their stock price will jump. Stock prices are based partly on expected future earnings and sales and so on.
I have seen a pharmaceutical company's stock price drop $10 in one night because they could net get a drug they were planning on selling approved for distribution by the FDA.
I'll leave the physics talk to the rest of you guys now.:) |
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| Acid Junkie |
| quote: | Originally posted by King_Mack
acid junkie, I thought a negative square root solution for the schqarzschild equation meant the existance of wormholes?
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no, since schwarzschield's equation is time symmetric (that is based on a spherically symmetric spacetime), a negative square root solution implies something that is exactly opposite to the solution that represents the possibility of black holes. a worm hole is not such a thing. thinking mathematically, a white hole would have to be something that would run BACKWARDS in time (in other words, a white hole would be in so-called negative time, which means its spacetime coordinates would be opposite to those of a black hole in our time). but a different spacetime continuum also implies that it would be located in a different universe. and here's where it gets a little tricky; it is true that white holes cannot possibly exist because they would contradict the second law of thermodynamics... but! in order for the previous statement to be correct, it has to be mentioned that their existence is unlikely in OUR universe. but what do we know about other universes? do they exist? if schwarzschield's equation is correct (which would be possible only if General Relativity itself is correct) then yes because a negative square root solution outside the horizon represents something more global than just a white hole - it representes another universe. the laws of thermodynamics as we interpret them may simply not work in such a universe at all. u see if spacetime is spherically symmetric, white holes (and worm holes) have to exist in order to complete the very geometry of schwarzschield's model. |
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| occrider |
| WTF? This was 5 months ago! |
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| DasBrotBesser |
| quote: | Originally posted by zarathustra
According to Einstein, faster than light travel is possible only if repulsive gravity existed. This is the basis of the theory of cosmic inflation. A Portuguese physicist named Joao Magueijo (I can't type the accents on the letters) has another idea about this. If the speed of light were faster in the past, it would also fit the theory. So, light might not be what we think it is... |
So i guess you read that article too, huh?
| quote: | | WTF? This was 5 months ago! |
LOL i didn't even notice that, but whatever cause OH MAN this stuff is right up my field! Good job on reviving this creon!
So uhh, dammit! i was gonna say something, but i can't remember it... how in annoying! but i do remember a question that i have. I've been trying to figure this sentence out from my textbook about Planck's Theory of Blackbody Radiation since the beginning of the semester (we're about 6 weeks in):
"If an object has a temperature of 1000 C, it glows with a red color, no matter what material it is made of. At higher termperatures, it glows orange, yellow, white, or even blue if the temperature is high enough." [now this is the sentence i was talking about (the other sentences were just the lead-in)] "At any temperature an object with a lower reflectivity glows more intensely at every wavelength, so that a black body, a model system that reflects no radiation at any wavelenth, has the maximum emissivity at every wavelength."
What the ?! I've read this sentence at least 50 or 60 times trying to decipher every word as i go along. It just seems so contradictory! Someone please explain this cause it's killin me!
also, uhh, i know this is mean but so good at the same time:
I know i'm gonna get it when it comes out! |
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| whiskers |
| quote: | Originally posted by DasBrotBesser
"If an object has a temperature of 1000 C, it glows with a red color, no matter what material it is made of. At higher termperatures, it glows orange, yellow, white, or even blue if the temperature is high enough." [now this is the sentence i was talking about (the other sentences were just the lead-in)] "At any temperature an object with a lower reflectivity glows more intensely at every wavelength, so that a black body, a model system that reflects no radiation at any wavelenth, has the maximum emissivity at every wavelength."
What the ?! I've read this sentence at least 50 or 60 times trying to decipher every word as i go along. It just seems so contradictory! Someone please explain this cause it's killin me!
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the way i see it, if you heat up a black body, it would be emitting more radiation than a non-black body. but you are right, whoever wrote this sentence was on crack, because it doesn't make any sense.
it still doesn't beat "given a truth table of n propositional variables, construct a disjunctive normal form of a compound proposition by taking the disjunction of conjunctions of the variables or their negations, with one conjunction included for each combination of valuses for which the compound proposition is true". i broke my brain reading that :D :D :D :D |
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| DrUg_Tit0 |
| quote: | Originally posted by DasBrotBesser
So i guess you read that article too, huh?
LOL i didn't even notice that, but whatever cause OH MAN this stuff is right up my field! Good job on reviving this creon!
So uhh, dammit! i was gonna say something, but i can't remember it... how in annoying! but i do remember a question that i have. I've been trying to figure this sentence out from my textbook about Planck's Theory of Blackbody Radiation since the beginning of the semester (we're about 6 weeks in):
"If an object has a temperature of 1000 C, it glows with a red color, no matter what material it is made of. At higher termperatures, it glows orange, yellow, white, or even blue if the temperature is high enough." [now this is the sentence i was talking about (the other sentences were just the lead-in)] "At any temperature an object with a lower reflectivity glows more intensely at every wavelength, so that a black body, a model system that reflects no radiation at any wavelenth, has the maximum emissivity at every wavelength."
What the ?! I've read this sentence at least 50 or 60 times trying to decipher every word as i go along. It just seems so contradictory! Someone please explain this cause it's killin me!
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Um, the sentence is pretty confusing. Basically a black body is a body that is absolutely non-reflective, meaning it absorbs all radiation that falls upon it. Then instead of reflecting, it radiates that absorbed radiation back as heat in a way discribed in the first sentence. The fact that it doesn't reflect any radiation back means it sucks it all up and uses it all for its own temperature emission. That's why you could say it has the maximum emissivity. A non black body would recieve just a fraction of the radiation while reflecting the rest and would therefore have weaker emissivity. |
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| occrider |
| quote: | Originally posted by DrUg_Tit0
Um, the sentence is pretty confusing. Basically a black body is a body that is absolutely non-reflective, meaning it absorbs all radiation that falls upon it. Then instead of reflecting, it radiates that absorbed radiation back as heat in a way discribed in the first sentence. The fact that it doesn't reflect any radiation back means it sucks it all up and uses it all for its own temperature emission. That's why you could say it has the maximum emissivity. A non black body would recieve just a fraction of the radiation while reflecting the rest and would therefore have weaker emissivity. |
Good explanation. I guess the confusion stemmed from the differences between emissivity and reflectivity. |
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| Cuervo79 |
| hey what about quantum physics? are there any theories in quantum physiscs that talk about time travel? |
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