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Planck Telescope Is Coolest Spacecraft Ever

timothy posted more than 5 years ago | from the that's-certainly-what-the-moon-rabbits-think dept.

Space 196

Hugh Pickens writes "Launched in May, BBC reports that Europe's Planck observatory has reached its operating temperature, a staggering minus 273.05C — just a tenth of a degree above what scientists term "absolute zero." and although laboratory set-ups have got closer to absolute zero than Planck, researchers say it is unlikely there is anywhere in space currently that is colder than their astronomical satellite. This frigidity should ensure the bolometers will be at their most sensitive as they look for variations in the temperature of the Cosmic Microwave Background (CMB) that are about a million times smaller than one degree — comparable to measuring from Earth the heat produced by a rabbit sitting on the Moon. Planck has been sent to an observation position around the second Lagrange point of the Sun-Earth system, L2, some 1.5 million km from Earth and Planck will help provide answers to one of the most important sets of questions asked in modern science — how did the Universe begin, how did it evolve to the state we observe today, and how will it continue to evolve in the future. Planck's objectives include mapping of Cosmic Microwave Background anisotropies with improved sensitivity and angular resolution, determination of the Hubble constant, testing inflationary models of the early Universe, and measuring amplitude of structures in Cosmic Microwave Background. 'We will be probing regimes that have never been studied before where the physics is very, very uncertain,' says Planck investigator Professor George Efstathiou from Cambridge University. 'It's possible we could find a signature from before the Big Bang; or it's possible we could find the signature of another Universe and then we'd have experimental evidence that we are part of a multi-verse.'"

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Did you ever notice ? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#28582761)

The word "genitalia" contains "italia".

Re:Did you ever notice ? (0, Offtopic)

eltaco (1311561) | more than 5 years ago | (#28583021)

apparently you've never heard of the company powergen, that went international and opened up an italian branch.
www.powergenitalia.com

rabit from the moon (0)

Hadlock (143607) | more than 5 years ago | (#28582785)

comparable to measuring from Earth the heat produced by a rabbit sitting on the Moon

Is anyone else dissapointed we don't already have this capability? I can stream Top Gear in HD from youtube in faster than real time but we lag this far behind in (optical? thermal?) imaging? I know the atmosphere creates a lot of optical distortion... but really? Not even a rabbit (which have unusually high body temps if I recall correctly)?

Re:rabit from the moon (1, Informative)

Anonymous Coward | more than 5 years ago | (#28582803)

Uh, yea. Atmopheric distrotion is bad enough for visible radiation...thermal would basically be a second level of distortion.

Re:rabit from the moon (4, Funny)

Valdrax (32670) | more than 5 years ago | (#28582837)

I just want to know how long the rabbit's been sitting there. I mean, is it still a living rabbit, and does it get hotter for a few seconds as it thrashes around without breath in the moon's almost nonexistent atmosphere?

Or do scientists just know how hot SPACE RABBITS get? When will the invasion come?

Re:rabit from the moon (2, Funny)

fuzzyfuzzyfungus (1223518) | more than 5 years ago | (#28582857)

Space rabbits are a minimal threat. The space vixens keep their population in check.

Re:rabit from the moon (4, Informative)

RyanFenton (230700) | more than 5 years ago | (#28582885)

According to Japanese and Aztek folklore [wikipedia.org] , a rabbit has been there for a long time. I could never really make out the face or the rabbit in the moon's craters when I look.

Ryan Fenton

Re:rabit from the moon (2, Interesting)

Ann Coulter (614889) | more than 5 years ago | (#28583435)

MUAD'DIB: the adapted kangaroo mouse of Arrakis, a creature associated in the Fremen earth-spirit mythology with a design visible on the planet's second moon. This creature is admired by Fremen for its ability to survive in the open desert. [1]

[1] Herbert, Frank. Dune. 1965.

Re:rabit from the moon (1)

nih (411096) | more than 5 years ago | (#28582939)

Its too late, the invasion has begun! [imdb.com]

The ESA is awesome. (-1, Troll)

Anonymous Coward | more than 5 years ago | (#28582971)

The European Space Agency [esa.int] (ESA) is an admirable organization. It has achieved numerous technological firsts.

Why have the Europeans achieved so much for humanity, yet the Africans have achieved so little?

Note that the ESA has a policy opposing affirmative action. Unlike NASA (in the USA), ESA does not give preferential treatment on the basis of skin color.

Re:rabit from the moon (4, Funny)

Anonymous Coward | more than 5 years ago | (#28583005)

I'm just disappointed they couldn't find a way to turn it into a car analogy instead of rabbits.

Re:rabit from the moon (1)

KillerBob (217953) | more than 5 years ago | (#28584015)

Volkswagen makes a model of car called the Rabbit.... what makes you so sure it isn't a car analogy?

Re:rabit from the moon (1)

maxume (22995) | more than 5 years ago | (#28583105)

Behind what?

Re:rabit from the moon (2, Funny)

El Cubano (631386) | more than 5 years ago | (#28583231)

comparable to measuring from Earth the heat produced by a rabbit sitting on the Moon

Is anyone else dissapointed we don't already have this capability?

I'm actually a little disappointed that this wasn't expressed in standard metric terms. I thought here on Slashdot, the agreed upon standard was something in terms of libraries of congress. Is there a conversion factor or something we can apply here?

Re:rabit from the moon (3, Funny)

Asclepius99 (1527727) | more than 5 years ago | (#28583393)

20 rabbits = 5 hares

Re:rabit from the moon (1)

Kratisto (1080113) | more than 5 years ago | (#28583445)

I dunno. What's the temperature of the library of congress? How long can it maintain that temperature if we put it on the moon, and for how long has it been on the moon?

Re:rabit from the moon (2)

Colourspace (563895) | more than 5 years ago | (#28583577)

Easy. Has slightly less temperature than a truck full of tapes on the highway, simple really.

Re:rabit from the moon (5, Insightful)

thrawn_aj (1073100) | more than 5 years ago | (#28584017)

comparable to measuring from Earth the heat produced by a rabbit sitting on the Moon

Is anyone else dissapointed we don't already have this capability? I can stream Top Gear in HD from youtube in faster than real time but we lag this far behind in (optical? thermal?) imaging? I know the atmosphere creates a lot of optical distortion... but really? Not even a rabbit (which have unusually high body temps if I recall correctly)?

Actually, that's an interesting question. It has been answered in this thread but I'd like to address a deeper issue here. Technical challenges usually come in two flavors, one which can be solved simply by making a device better and better and the other, which has to do with the signal you're trying to measure just not being there (or is otherwise masked by "noise"). I put "noise" in quotes because people always assume the signal can be separated from the noise. Not so. In most cases, you have to know the source of the noise to reliably subtract it out. In other cases, you can be lucky and the noise will be random so that greater averaging of the data filters out the noise automatically. For ALL other cases, people have to resort to making assumptions about the noise, which means that the "filtered signal" you end up with has (sometimes huge) contributions from the person who made the assumption. Is it a rabbit or an artifact of my assumptions?

This particular question you raise is in that final category. There just isn't enough signal there that is distinguishable from the surrounding crap for you to tell with any certainty that you have rabbits on the moon and not a migratory bird flock here in the sky. You could always throw money at the problem (in principle) by having a dozen weather satellites constantly monitoring the patch of atmosphere in direct line of sight between you and the moon and feeding you detailed real-time data of temperature, pressure, index of refraction, chemical composition of air(/dust) in there (affects absorption/reflection/transmission). THEN, you MIGHT stand a good chance of catching a glimpse of your elusive rabbit.

Technology can always be improved. Ambient conditions will always be the ultimate threshold for the actual utility of that technology.

That is not to say that a particular phenomenon always stays of out of reach. One simply realizes that certain constraints stated in the problem are actually ridiculous. For instance, if the goal was really to observe rabbits on the moon, the constraint that the instrument be on the earth is highly artificial. Instead, one would relax that constraint, put a satellite above the atmosphere, satisfy one's rabbit fetish and the problem's solved :).

Re:rabit from the moon (1)

MillionthMonkey (240664) | more than 5 years ago | (#28584021)

Well as we all know:

Hey diddle diddle,
The cat and the fiddle,
The cow jumped over the moon,
The little dog laughed to see such fun,
And the dish ran away with the spoon.

It seems to be well within the capability of current measurement techniques to determine whether bovines are leaping over natural satellites, so we should be able to figure out if a rodent is sitting on one.

That's pretty cool (0)

Anonymous Coward | more than 5 years ago | (#28582789)

I don't know what else to say about that.

Don't think so. (3, Funny)

nebaz (453974) | more than 5 years ago | (#28582795)

They call that a cool space craft? It doesn't even have warp drive, let alone quantum torpedoes. It doesn't even have anything onboard to which you could apply the phase "reverse the polarity". Cool. Bah!

Re:Don't think so. (0)

Anonymous Coward | more than 5 years ago | (#28582859)

"It doesn't even have anything onboard to which you could apply the phase "reverse the polarity".

I would be surprised if it didn't have a battery somwhere...

By the way, didn't the US military say that they were going to take and hold the Legrange points to prevent their use by foreigners, since they were strategically important? Surely we should be nuking Plank, to assert our manifold destiny to grab anything that's grabable...

Re:Don't think so. (1)

fuzzyfuzzyfungus (1223518) | more than 5 years ago | (#28582867)

It might actually have one or more peltier devices, which could definitely merit the phrase "reverse the polarity".(though, given the needs of the experiment, I suspect that reversing the polarity would be a terrible plan...)

I'll bet there's plenty of polarity to reverse (1)

Weedhopper (168515) | more than 5 years ago | (#28582873)

They call that a cool space craft? It doesn't even have warp drive, let alone quantum torpedoes. It doesn't even have anything onboard to which you could apply the phase "reverse the polarity". Cool. Bah!

Dude, you can reverse the polarity on anything with a DC circuit. Sometimes, with spectacular results.

Re:I'll bet there's plenty of polarity to reverse (2, Funny)

Mitchell314 (1576581) | more than 5 years ago | (#28582907)

In other news, the coldest telescope became the hottest telescope upon the discovery of two coincidental mistakes where all analog switch were labeled backwards and the purchased fuses closed on failure.

Re:Don't think so. (1)

Greyfox (87712) | more than 5 years ago | (#28583279)

Hmm... If you reverse the polarity of the bolometers, you might be able to CAUSE galactic background noise rather than measuring it! This would disturb the subspace plextrons the borg craft uses for propulsion, causing it to self destruct!

Re:Don't think so. (5, Interesting)

Artifakt (700173) | more than 5 years ago | (#28583403)

Neat idea, taken a little farther. An advanced civilization prevents a more primitive one from developing advanced physics by making astrophysical observations look funny locally. The primitives assume the weak anthropic principle holds, come up with all these really strange theories about cosmic strings, dark energy and such, and never become competition.

Re:Don't think so. (1)

zMaile (1421715) | more than 5 years ago | (#28583703)

You sir, just blew my mind. We've been looking for the wrong things this whole time! it all makes sense now.

Re:Don't think so. (1)

jmv (93421) | more than 5 years ago | (#28583727)

It doesn't even have anything onboard to which you could apply the phase "reverse the polarity"

Of course it does. I heard it's powered by AA batteries.

Re:Don't think so. (1)

syousef (465911) | more than 5 years ago | (#28584121)

It doesn't even have anything onboard to which you could apply the phase "reverse the polarity".

You can reverse the polarity on anything electrical. Just swap the positive and negative terminals. Don't ever expect to use many of those things you do that to ever again though. Most of the things that die will wimper but some higher voltage things will get dangerous and explode.

Now that's COOL.....if....... (1)

spazekaat (991287) | more than 5 years ago | (#28582807)

If the rabbits don't have the Holy Hand Grenade in their arsenal..... :-)))

(Monty Python and the Holy Grail for all you unwashed masses....)

But, seriously, being to cool down the detectors so low is great, although I don't think that it is a "first" (citation needed).
Didn't COBE have super-cooled detectors also? I'm too lazy to look that up..... ;-)

One Planck telescope for mankind... (1)

MRe_nl (306212) | more than 5 years ago | (#28582811)

That's a pretty small telescope you have there, and it doesn't last very long either ; ).

Signature (1, Funny)

Anonymous Coward | more than 5 years ago | (#28582821)

"Sorry for the Inconvenience"

Planck telescope (4, Funny)

Bromskloss (750445) | more than 5 years ago | (#28582855)

The Planck telescope is the smallest telescope that, according to our current understanding of nature, it is meaningful to speak about. This property sets the Planck telescope apart as the natural unit (also called Planck unit) for telescopes.

Re:Planck telescope (2, Funny)

Eudial (590661) | more than 5 years ago | (#28583039)

The Planck telescope is the smallest telescope that, according to our current understanding of nature, it is meaningful to speak about. This property sets the Planck telescope apart as the natural unit (also called Planck unit) for telescopes.

I think the technical term is telescope quantization. Telescopes can only exist as integer multiples of the Planck telescope.

Worst metaphor ever? (4, Insightful)

mellon (7048) | more than 5 years ago | (#28582871)

A rabbit sitting on the moon will be at a much different temperature than its surroundings, not a millionth of a degree kelvin. The only thing interesting about measuring the temperature of a rabbit on the moon is resolution, not sensitivity. So essentially completely the opposite of what the Planck telescope does.

Sorry, just had to release my inner pedant - this was too good to resist.

Re:Worst metaphor ever? (2, Funny)

RichardJenkins (1362463) | more than 5 years ago | (#28582929)

A rabbit sitting on the moon will be at a much different temperature than its surroundings

Not for very long. How's that for pedantry?

Re:Worst metaphor ever? (1)

mellon (7048) | more than 5 years ago | (#28583833)

Presumably the rabbit is protected somehow, or else it wouldn't be sitting. Of course, that protection would probably smooth out the variance in the amount of energy being radiated, and so make the measurement process more interesting...

Re:Worst metaphor ever? (3, Informative)

Anonymous Coward | more than 5 years ago | (#28582935)

heat != temperature.

The summary said "heat produced by a rabbit sitting on the Moon". Somehow that went through your brain and came out as "measuring the temperature of a rabbit on the moon". So the problem is you, not the metaphor.

Re:Worst metaphor ever? (1)

scjohnno (1370701) | more than 5 years ago | (#28583653)

Mod parent up. The summary said to measure the rabbit from Earth, the whole point of which is to illustrate the distance involved. At such a distance, the radiant heat from the rabbit will have weakened such that it would be nearly indistinguishable from other sources much closer. This is where you need sensitivity.

Re:Worst metaphor ever? (1)

zMaile (1421715) | more than 5 years ago | (#28583761)

It's a metaphor?

Re:Worst metaphor ever? (1)

mellon (7048) | more than 5 years ago | (#28583819)

Er, no. The variation in temperature between the rabbit and its surroundings is substantial. The variance being measured in the microwave background are tiny. The distinction between heat and temperature here doesn't matter (or if it does, you haven't yet explained why).

Re:Worst metaphor ever? (0)

Anonymous Coward | more than 5 years ago | (#28583887)

They use bolometers. Read the link. Bolometers measure incoming energy, and it doesn't matter if the energy comes from something hot or something cold.

The rabbit wasn't a metaphor. Planck can *actually* detect a rabbit on the moon by its heat. The rabbit size won't be resolved, but enough watts will reach the instruments.

Re:Worst metaphor ever? (3, Funny)

Ambiguous Coward (205751) | more than 5 years ago | (#28582937)

The only thing interesting about measuring the temperature of a rabbit on the moon is resolution

Well yeah, that and the obvious question of "what the hell is a rabbit doing on the moon, and how did it get there?"

Re:Worst metaphor ever? (2, Funny)

Jeek Elemental (976426) | more than 5 years ago | (#28582981)

Maybe its measuring the temperature of a human on earth?

Re:Worst metaphor ever? (1)

Lehk228 (705449) | more than 5 years ago | (#28583045)

obviously it is suffering an agonizing demise since it doesn't have a pressure suit, O2 supply, or thermal protection.

Re:Worst metaphor ever? (1)

Asclepius99 (1527727) | more than 5 years ago | (#28583425)

Actually all you need is a fishbowl, oxygen tank, and a wetsuit.

Re:Worst metaphor ever? (1)

KillerBob (217953) | more than 5 years ago | (#28584061)

If you're going to MacGyver an exposure suit to keep the rabbit alive, you'll probably need some duck tape. Wetsuits don't form a watertight seal, let alone an airtight seal, so you need some way to prevent the air from escaping from the fishbowl.

Re:Worst metaphor ever? (1)

maxume (22995) | more than 5 years ago | (#28583141)

Too much asparagus.

Re:Worst metaphor ever? (2, Funny)

Mogster (459037) | more than 5 years ago | (#28583239)

Well yeah, that and the obvious question of "what the hell is a rabbit doing on the moon, and how did it get there?"

Obviously it should've taken that left turn at Albuquerque =)

Re:Worst metaphor ever? (1)

ozbird (127571) | more than 5 years ago | (#28584043)

Well yeah, that and the obvious question of "what the hell is a rabbit doing on the moon, and how did it get there?"

The Goodies [wikipedia.org] dunnit.

Re:Worst metaphor ever? (0)

Anonymous Coward | more than 5 years ago | (#28583295)

The rabbit will be at the temperature as its surroundings, because without an atmosphere, it's dead.

Why a rabbit? (1)

Mishotaki (957104) | more than 5 years ago | (#28582877)

Really, it doesn't have a reason to go on the moon.... if they would give the mouse for example, i'm sure that little critter would love to be on the moon much more than a rabbit, so that it can eat all the cheeze there is there!

Temperature scale? (-1)

Anonymous Coward | more than 5 years ago | (#28582893)

variations in the temperature of the Cosmic Microwave Background (CMB) that are about a million times smaller than one degree

So approximately minus 999,999 degrees? What scale is that in?

NPOV (3, Insightful)

michaelmalak (91262) | more than 5 years ago | (#28582925)

just a tenth of a degree above what scientists term "absolute zero."

This is where the so-called "neutral point of view" ceases to be useful.

Re:NPOV (1)

Weedhopper (168515) | more than 5 years ago | (#28582975)

I scratched my head over this, too.

Why is "absolute zero" in quotes? And what do "people" who aren't "scientists" call "0" on the "temperature scale" that "scientists" term "Kelvin"?

Re:NPOV (2, Interesting)

michaelmalak (91262) | more than 5 years ago | (#28583011)

The idea of absolute morality is so forbidden in mainstream media that anytime anyone uses the word "absolute", it has to be portrayed in a relativistc sense. So in this case, scientists believe in some sort of "absolute zero", but that doesn't mean everyone does, and thus the myth that there are no absolutes is preserved.

Re:NPOV (0, Flamebait)

Anonymous Coward | more than 5 years ago | (#28583211)

You're an absolute moron for confounding something simple like temperature with something like morality. I don't know how many logical fallacies you made there, but I'm absolutely sure you're a demented tool.

Re:NPOV (1)

muridae (966931) | more than 5 years ago | (#28583051)

I think it was a wikipedia meets special relativity pun. Since there can be no absolute reference frame, how can there be an "absolute zero". Maybe, somewhere outside our 4 dimensional reference, an object we think is at complete rest is vibrating and contains energy. Then you match that with Wiki's intended neutral point of view . . .

And if it wasn't a really horrible pun, then maybe the GP was trolling

Re:NPOV (0)

Anonymous Coward | more than 5 years ago | (#28583955)

Well its absolute to all data known because we don't know of nor have meaningful data of any other dimension.

Re:NPOV (1)

Lehk228 (705449) | more than 5 years ago | (#28583123)

summary reads like it was meant for CNN.com not slashdot.org. I am certain that nobody with a slashdot account would be both ignorant of what absolute zero is and incapable of JFGI

Re:NPOV (0)

Anonymous Coward | more than 5 years ago | (#28583311)

I didn't know what JGFI stood for... the first two google matches indicate Jakarta Growth Fund Inc. The third was hard to decipher. It looks like something to do with certification of electronic components, so I'm guessing you mean the summarizer can't certify electronics components right?

Re:NPOV (1)

pjt33 (739471) | more than 5 years ago | (#28583223)

I'm not sure that's even the worst infelicity of the summary. The start, "Launched in May, BBC" establishes that BBC (perhaps "the BBC") was launched in May.

Planck to measure variations? (0)

Anonymous Coward | more than 5 years ago | (#28582931)

I hope the Cosmic Microwave Background temperature doesn't turn out to be constant...

some 1.5 million km from Earth? (-1, Redundant)

frovingslosh (582462) | more than 5 years ago | (#28582965)

Planck has been sent to an observation position around the second Lagrange point of the Sun-Earth system, L2, some 1.5 million km from Earth

Wait a second, the earth is roughly 93 million miles from the Sun. It's orbit should cover about about a 584 million mile circumference. And yet this claims a Lagrange point of the Sun-Earth system is only 1.5 million km from Earth (.932 million miles). How can I have faith in anything this says when it reports the location of a Lagrange point so incorrectly? It's off by over 2 orders of magnitude!

Re:some 1.5 million km from Earth? (4, Informative)

BeeRockxs (782462) | more than 5 years ago | (#28583007)

L2 is behind the earth, as seen from the sun. And the distance given is correct.

Re:some 1.5 million km from Earth? (2, Informative)

Mt._Honkey (514673) | more than 5 years ago | (#28583061)

The distance in the article is correct. Plank is at L2. Perhaps you were thinking about L4 or L5 (both 1 AU away), or L3 (~2 AU away).

Wikipedia has an excellent article [wikipedia.org] describing each of the Legrangian points and why each of them is pseudo-stable.

Re:some 1.5 million km from Earth? (1)

LakeSolon (699033) | more than 5 years ago | (#28583095)

You did a lot of typing in your post. I think perhaps you could have saved a lot of it in your quest to enlightenment if you'd have chosen a text field on a different web page. May I suggest http://google.com/ [google.com] and the phrase "earth sun l2"? The first link even has a very descriptive map. http://en.wikipedia.org/wiki/Lagrangian_point [wikipedia.org]

In case you're wondering, (1)

robogobo (891804) | more than 5 years ago | (#28583047)

that's colder than a witch's titty (-273.04C).

Now... (0)

Anonymous Coward | more than 5 years ago | (#28583069)

... is the rabbit alive or not? And who wants to look?

Algorithm (1, Funny)

Anonymous Coward | more than 5 years ago | (#28583121)

while (measured_age_of_the_universe != 6000)
        launch a better satellite;

Why is it so hard for people to understand? (1, Insightful)

leehwtsohg (618675) | more than 5 years ago | (#28583171)

Why is it so hard for people to understand that there is no "before the big bang"? Time was created at the big bang. There is no "before time began". Before time, there is no before. A bit like there was no spelling bee champion 65 million years ago. Maybe very little like that. Or maybe a bit like asking what is west of the moon. Hmmm... ok, very little like that, too. How about like asking at what date 13 became a prime number? Yes, more like that. You get the gist. Time is part of our universe. The big bang created the universe, space and time together.
If there was no big bang, then maybe there was something before whatever was then. But if there was a big bang, there was nothing before that.

Re:Why is it so hard for people to understand? (1)

Deadstick (535032) | more than 5 years ago | (#28583219)

People just don't read Gertrude Stein any more.

rj

Re:Why is it so hard for people to understand? (2, Insightful)

Aris Katsaris (939578) | more than 5 years ago | (#28583271)

"Why is it so hard for people to understand that there is no "before the big bang"? Time was created at the big bang."

That's certainly an interesting hypothesis. In what way do you propose we test it out?

Re:Why is it so hard for people to understand? (0)

leehwtsohg (618675) | more than 5 years ago | (#28583335)

Sorry. It isn't a hypothesis. It is something that should be true or false by definition. Like you can't test if a circle has a start and an end. It could be that I am babbling out of the wrong part of my anatomy, and I certainly should have said something like: "if I understand what the big bang is supposed to be, its geometry, then time began at the big bang..."
How do you test the hypothesis that there was no date at which 13 became a prime number?

And, I didn't mean to say anything against the spacecraft! It will certainly teach us a lot about the big bang, and whether it happened or not, and probably teach us many things that we didn't expect. And it can probably also teach us much about what time is.

Re:Why is it so hard for people to understand? (1)

Aris Katsaris (939578) | more than 5 years ago | (#28583609)

"It is something that should be true or false by definition."

I don't know anything about the definition of Big Bang including the idea that time began with it. As far as I know Big Bang is the name for the explosive expansion of all matter in the universe at some point in the past from a primeval dense condition.

That time originated there as well is just a theory, nothing definitional about it as far as I know.

Re:Why is it so hard for people to understand? (0, Interesting)

Anonymous Coward | more than 5 years ago | (#28583717)

"It is something that should be true or false by definition."

I don't know anything about the definition of Big Bang including the idea that time began with it. As far as I know Big Bang is the name for the explosive expansion of all matter in the universe at some point in the past from a primeval dense condition.

That time originated there as well is just a theory, nothing definitional about it as far as I know.

Well, he's wrong in that the big bang is by definition true or false. There are many different aspects of the theory that do indeed require testing and as to the how do we test these things, that's a very good question on your part.

You did, however, made me cringe when you used the "just a theory" line. It implies you don't understand the meaning of "theory" in science. It's not the same as the meaning of the word outside scientific circles. In science, a "theory" is basically as close to truth that you can get apart from direct observation. We accept the fact that nothing can ever be proven to be true beyond the shadow of a doubt, but if a theory gives accurate predictions, is falsifiable but has not been falsified, then it can't get better than that until you come across something that the theory does not explain. That's not a bad thing, that's a great thing: it allows us to learn more about the universe, refine the theory, and come up with something that is even closer to the truth.

The big bang is not the explosive expansion of all matter in the universe from a point. It's the explosive expansion of all spacetime. Don't think of it as matter shooting off from a single point in the universe into already existing space. Think of it as the space between particles growing. The universe used to be infinitely small (and thus infinitely dense)--as in, there was no volume, no place for matter to go into. Then there was more space. The center of the big bang is right where you are standing now. Right where I'm standing now. Everywhere is the center of the big bang, the dimensions of the universe just got bigger...and that includes time. So, the grandparent is right that, in a way, it does not make sense to talk about "before the big bang." However, the term "before the big bang" is usually how scientists refer to conditions upon which a big bang occurs. There's a theory that we are not the only universe, that big bangs happen all the time, and this environment where big bangs occur is what these scientists typically mean when they say "before the big bang."

So yes, the definition of the Big Bang does include the idea that time began with it, and although being the currently accepted theory means quite a lot more than "just a theory" would imply, it doesn't mean we shouldn't test the hell out of it. Look this stuff up. Plenty of material available, and it's all interesting stuff.

Re:Why is it so hard for people to understand? (1)

arminw (717974) | more than 5 years ago | (#28583869)

....There's a theory that we are not the only universe, that big bangs happen all the time....

Too bad that is not a theory but a conjecture, because it is not falsifiable and does not give any predictions of anything. No predictions based on this so-called theory can be made.

If you believe in the law of cause and effect, then the so-called Big Bang has to have a cause. If time began with the Big Bang, then it's cause has to be eternal, beyond time, before time, God. The Bible tells us that God is eternal, he just is, the great I am.

Re:Why is it so hard for people to understand? (1)

arminw (717974) | more than 5 years ago | (#28583821)

...there is no "before the big bang"?...

Bible says that God is eternal that is he has always existed and he created the universe. He may well have started it off with a bang. God is eternal and is not subject to time, space, gravity or any other quantifiable thing in this universe. This cannot be tested but can only be believed or disbelieved.

Re:Why is it so hard for people to understand? (0, Flamebait)

Aris Katsaris (939578) | more than 5 years ago | (#28583875)

"Bible says that God is eternal that is he has always existed"

Why do you assume I'll care about what the Christian Bible says, even to disbelieve in it?

I'm not burdening you with the Aztec tales of creation, to tell you you can only believe or disbelieve in them -- why? Because you most probably don't care about the Aztec tales of creation, or the Babylonian tales of creation, or the Chinese tales of creation. You probably don't care enough to even "disbelieve" in them.

So, please spare me the Judeochristian parochialism.

Re:Why is it so hard for people to understand? (2, Insightful)

fatski (1137813) | more than 5 years ago | (#28583321)

Unless our universe exists within something larger, with its own time. If there were universes prior to this one in that larger space then there would have been something before the big bang, regardless of our universes local time. You might not think so, but really, nobody knows.

Re:Why is it so hard for people to understand? (0, Troll)

arminw (717974) | more than 5 years ago | (#28583957)

...If there were universes prior to this one....

So where along the infinite progression of universes do we come in? Somewhere in there has to be a beginning, the first universe, even if we truly are one of many. Other than being distasteful to the rebellious human spirit which wants to be responsible to no one, what is the big deal of postulating an eternal being, God? The reason I said distasteful, is because as soon as we admit such a God, we feel we may be responsible to him and somehow innately feel that we don't measure up to God's standards.

The Bible says that it is appointed unto men to die once and after that comes judgment. (Hebrews 9:27) It is not possible to dispute the fact of death, but many people do dispute the second part of this sentence. It is the secret fear of the outcome of this judgment that causes humans with feigned certainty to deny the existence of God.

Re:Why is it so hard for people to understand? (2, Informative)

khchung (462899) | more than 5 years ago | (#28584139)

For your statement to make sense, you assumed the same property "time" exists within and outside the universe, and that it made sense to connect the two. It is like saying since Earth existed within something larger, there might be something due North of Earth's North Pole.

Unfortunately, North/South is a local property of Earth, while there is plenty space above the North Pole, you cannot go more north from the North Pole. Similarly, spacetime is a property of our observable universe, and that property breaks down at Big Bang. Trying to simply extrapolating spacetime from the universe to beyond is like trying to reach space by just keep going North on the Earth.

Re:Why is it so hard for people to understand? (2, Insightful)

V50 (248015) | more than 5 years ago | (#28583327)

Why is it so hard for people to understand that there is no "before the big bang"? Time was created at the big bang. There is no "before time began". Before time, there is no before. A bit like there was no spelling bee champion 65 million years ago. Maybe very little like that. Or maybe a bit like asking what is west of the moon. Hmmm... ok, very little like that, too. How about like asking at what date 13 became a prime number? Yes, more like that. You get the gist. Time is part of our universe. The big bang created the universe, space and time together.
If there was no big bang, then maybe there was something before whatever was then. But if there was a big bang, there was nothing before that.

So basically what you're saying is that in the beginning, there was nothing, which exploded.

And you wonder why people have a hard time grasping current big bang theory. :-)

Re:Why is it so hard for people to understand? (1)

leehwtsohg (618675) | more than 5 years ago | (#28583355)

I'm saying there is nothing "before" a space-time singularity...

But, yes, I certainly don't grasp it.

Re:Why is it so hard for people to understand? (0)

Anonymous Coward | more than 5 years ago | (#28583657)

But consider f(t) = 1/sqrt(t) and f(t) = 1/t^2. Both are singularities (go to infinity as t->0).

You can't draw 1/sqrt(t) left of t=0 without involving complex numbers, but you can draw 1/t^2 left of t=0.

It's just not clear to us why you're so sure the universe is of the first type.

Re:Why is it so hard for people to understand? (0)

leehwtsohg (618675) | more than 5 years ago | (#28583781)

As far as I understand, according to general relativity (and we know something is wrong with GR), time has to start at the singularity of the Big Bang.
I don't have a good reference for the source of my info on this -- different talks in different places, but this seems to have a good summary:
http://www.hawking.org.uk/index.php/lectures/62 [hawking.org.uk]

But I realized now that I mixed up a pet peeve of mine with something that doesn't have to do with it.

The problem I had was with people who answer to the statement: "time started at the big bang" with the question: "but what was before that"?
Since our experience states that there must be something before anything.

And, general relativity states that time started at the big bang. So I just followed he logic saying that if time started at the big bang, then the question of what was before the big bang has no meaning.

But, general relativity doesn't have exclusivity on the big bang. A better theory might say that the universe expanded from something that was not a singularity, or maybe was a singularity through which timelines can pass, or something else that I/we don't understand yet, and then there would be a meaning to the question what was before the big bang.

I was wrong. An observation might tell us about the structure of the big bang, to cause us to conclude that there was indeed something before the big bang.

(So only according to GR there is no meaning to the question)

Re:Why is it so hard for people to understand? (0)

Anonymous Coward | more than 5 years ago | (#28583341)

They're probably mean hammer time, the time that our time is embedded in.
Like your time perception started when you were born from your mother, the time of our universe started when it was born from hammer space.

Please don't talk about stuff you obviously know nothing about..

Re:Why is it so hard for people to understand? (1)

leehwtsohg (618675) | more than 5 years ago | (#28583407)

Why not? I can learn so much if I do.

"One may say that time had a beginning at the big bang, in the sense that earlier times simply would not be defined."
[Stephen Hawking, A Brief History of Time (New York: Bantam, 1988), pp. 8-9.]

Obviously, taken out of context.

But, in this "hammer time" (I never heard that phrase), which direction would an egg break to little pieces? Which direction would entropy increase? Is there an answer to this, otherwise, I have a hard time telling what is before, and what is after.

Re:Why is it so hard for people to understand? (1)

CosmeticLobotamy (155360) | more than 5 years ago | (#28583409)

They're probably mean hammer time, the time that our time is embedded in.

Stop. Hammer time?

Re:Why is it so hard for people to understand? (1)

Chuck Chunder (21021) | more than 5 years ago | (#28583427)

Because it is unintuitive and because our language is limited. You yourself just wrote:

Before time, there is no before

Our language relates to the universe we live in so all we have is words like "before" whether we are talking about time or a causally related chain of states. For us they are the same thing.

You may be right about time as we know it not existing until the big bang (and I say "may" on purpose, your statement was rather definitive for something that is really on the edge of our theory and understanding).

That doesn't mean there wasn't something else which, in a causal sense, existed 'before' the big bang and resulted in it. It's difficult to talk about and difficult to conceptualise because both our language and science are based on describing, analyzing and explaining the universe as we do experience it. When we approach something fundamentally different from what we experience it gets very difficult indeed.

Re:Why is it so hard for people to understand? (1)

leehwtsohg (618675) | more than 5 years ago | (#28583475)

You are right. It could be that it is more like a question about what could have caused the big bang, or why did the big bang happen. Or if there was something that could effect HOW the big bang happened.

Even then, causality and time are so closely related....

Re:Why is it so hard for people to understand? (2, Funny)

jmv (93421) | more than 5 years ago | (#28583737)

I'm pretty sure what happened before the big bang is similar to what will happen after eternity.

Re:Why is it so hard for people to understand? (0)

Anonymous Coward | more than 5 years ago | (#28583747)

And yet people still ask who created God.

Re:Why is it so hard for people to understand? (1)

Dunbal (464142) | more than 5 years ago | (#28583841)

and then who created the guy that created "god".... etc.

Re:Why is it so hard for people to understand? (1)

arminw (717974) | more than 5 years ago | (#28583807)

...The big bang created...

So who created the Big Bang? The Bible says God created the Universe and that God has always existed. The Bible says that God created the universe out of nothing and scientists say that the Big Bang came from a singularity. Where does the singularity come from?

Re:Why is it so hard for people to understand? (1)

leehwtsohg (618675) | more than 5 years ago | (#28583853)

[If people where commenting that I don't know what I'm talking about before, now I really am just going wild - but hey, this IS /.]

Since time is part of the universe, the universe did not start to exist when time began. Existence of the universe and time have nothing to do with one another.

My personal view is that you can think of many many possible universes. (and there are even more you can't think of). Of all these, only ours seems to exist. Why do we think this one does exist, and the other ones we aren't really sure about? Because we exist in it, and we observe it. So, why does our universe exist? Because we are in it. Actually, that is the only evidence we have that it exists. And, a not logically following conclusion from all of that is that if any of these other virtual universes holds things "sufficiently similar to us", who "claim to observe their universe", then their universe, for them, also exists.

Now find how one can try to test this hogwash.

Go north from the North Pole (2, Insightful)

khchung (462899) | more than 5 years ago | (#28584101)

A simpler analogy would be to try to go north from the North Pole.

Obligatory (0)

Anonymous Coward | more than 5 years ago | (#28583715)

I, for one, welcome our lunar rabbit overlords.

Re:Obligatory (1)

Dunbal (464142) | more than 5 years ago | (#28583823)

In soviet russia, moon rabbit measures you!

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