Senate What are the greatest mysteries in science?

The point of the LHC as I understand it is to determine what the conditions were after the Big Bang. Problem is, the Big Bang itself was not the start of it all. There was Inflation which may have caused the Big Bang and happened after it.

Since there is now debate going on as to how exactly the Universe began, how can we determine a Unified Theory until we solve this problem? Big Bang suggests there was nothing beforehand, that the Universe started from an infinitely small point. In mathematics, infinity is basically giving up, or cheating. This does not provide a satisfactory answer.
"Everything from nothing" is God-talk, it doesn't work.

Finding out how particles behaved at a certain point in time will help, but I don't think the LHC will tell us much about gravity.

There is also Quantum Gravity.

 

Inflation came after the Big Bang. There may have been a Before The Big Bang but that has nothing to do with Inflation.

 

So, here's an article that claims gravity might just not exist, and really just be another effect of the laws of thermodynamics. I've also read hypotheses that "time" may not truly exist either, at least not in the way we think. What do our JC scientists think of this? I'm always interested in anything that includes thinking outside the box, like this.

Also, don't know if I posted this before, but here is the Standard Model of Fundamental Particles and Interactions, for reference:

[image=http://www.cpepweb.org/images/chart_2006_4.jpg]



EDIT:

I did post an older illustration of it, back on the first page

 

Anyone who can't watch BBC's Horizon on TV, the recent episode What Happened Before the Big Bang?, it is available in 6 parts on youtube if anyone wants to check it out. It states a number of interesting new ideas.

 

Oh I rememeber this story from a few months ago. My only thing is this guy better bring some really badass evidence because GR has yet to be proven wrong every time it's tested.

 

Time is really only a concept invented by humans. After all, animals sleep and wake up according to daylight & darkness, not passage of time. To them time is not important.

 

Time is as much a physical quantity as space is.

As for your example about animals, waking up "according to daylight and darkness" has everything to do with the passage of time.

 

That besides, it's wrong. While most animals are entrained to the prevailing light-dark cycle, many also have a free-running internal clock. Humans have one that sits at around 25 hour cycles. Free-running rhythms have also been found in bumblebees, rodents, and some species of plants.

 

How is time a "physical" quantity? There is no "chronon" particle that has been theorized (outside of old Doctor Who mythology ), and time itself is relative.

How can it have physicality? Are you refering to a "dimension" of time?

Peace,

V-03

 

Short answer: Yes, he may very well be.

Long answer: http://en.wikipedia.org/wiki/Minkowski_space

 

Time is a physical quantity the same way Space is a physical quantity. Space has no theoretical particle either, and Space is also relative (Einstein's "general relativity" theory of spacetime). Time is the fourth dimension, in addition to height, width, depth.

At least that's what currently-accepted theories of science say.



Since we're talking about time, what does everyone here think is a good definition of "Time"?

I've always gone with "the dimension that measures change." (As the three spatial dimensions are "the dimension that measures height/width/depth")

With the definition of "Change" being: a difference emerging in the positions of matter-energy within the three spatial dimensions.

 

I always liked Stephen Hawking's interpretation that it is the direction in which entropy increases.

 

[image=http://graphics8.nytimes.com/images/2010/11/10/science/space/10galaxy/10galaxy-articleLarge.jpg]

Two GIANT gamma-ray bubbles erupting from the Milky Way's galactic core

Something big is going on at the center of the galaxy, and astronomers are happy to say they don?t know what it is.

A group of scientists working with data from NASA?s Fermi Gamma-Ray Space Telescope said Tuesday that they had discovered two bubbles of energy erupting from the center of the Milky Way galaxy. The bubbles, they said at a news conference and in a paper to be published Wednesday in The Astrophysical Journal, extend 25,000 light years up and down from each side of the galaxy and contain the energy equivalent to 100,000 supernova explosions.

?They?re big,? said Doug Finkbeiner of the Harvard-Smithsonian Center for Astrophysics, leader of the team that discovered them.

The source of the bubbles is a mystery. One possibility is that they are fueled by a wave of star births and deaths at the center of the galaxy. Another option is a gigantic belch from the black hole known to reside, like Jabba the Hutt, at the center of the Milky Way. What it is apparently not is dark matter, the mysterious something that astronomers say makes up a quarter of the universe and holds galaxies together.

?Wow,? said David Spergel, an astrophysicist at Princeton who was not involved in the work.

?And we think we know a lot about our own galaxy,? Dr. Spergel added, noting that the bubbles were almost as big as the galaxy and yet unsuspected until now.

Jon Morse, head of astrophysics at NASA headquarters, said, ?This shows again that the universe is full of surprises.?

Wow, that's huge! I wonder how we could have missed it before, and if this will change any theories about galaxies and the universe.

The article doesn't consider it, but could this giant, galactic energy-field really account for the missing stuff we hypothesized would be dark matter? It must certainly change the equations, at least.

 

My offhand thought is that there's no way it accounts for dark matter. For dark matter, you're looking at roughly 4 times the amount of dark matter than there is regular matter. Something like this is energy, firstly, and so in terms of mass won't represent nearly that much mass, I don't think.

 

I still believe black holes are the great mystery of our time. Scientists seems to think such a phenomenon can be related to the creation of our universe.. There is very much talk in the science world the past years about everything that is dark
Dark matter, Dark energy, Black holes.. I hope we will soon discover parts of these mysteries since they seem to be so decisive to our understanding of cosmos.

 

That picture is phenomenal.

 

Sometimes I wonder if astrophysicists are in it for the gigantic numbers.

I'm certainly curious as to what's producing this phenomenon, and I trust they're going to start looking into it. However, I'm going to tentatively agree with Lowbacca in thinking that this is probably unrelated to dark matter.

 

Theory of Everything: Holy Grail or Fruitless Pursuit?

http://www.livescience.com/13129-physics-string-theory.html

Einstein died before completing his dream of creating a unified theory of everything. Since then, physicists have carried on his torch, continuing the quest for one theory to rule them all.

But will they ever get there? That was the topic of debate when seven leading physicists gathered here at the American Museum of Natural History for the 11th annual Isaac Asimov Memorial Debate.

The quest for a theory of everything arises because two of the most celebrated, successful theories in physics are contradictory.

The theory that describes very big things ? general relativity ? and the theory that describes very small things ? quantum mechanics ? each work amazingly well in their own realms, but when combined, break down. They can't both be right.

And we can't just sweep that fact under the rug and continue to use them each as they are, because there are some cases in which both theories apply ? such as a black hole.

"Its size is small in terms of length; its size is large in terms of mass. So you need both," explained Brian Greene, professor of physics and mathematics at Columbia University.

Scientists hope that a unified theory would resolve this incompatibility, and describe anything and everything in the universe in one fell swoop.

The article continues to describe how two popular possibilities for the TOE are string theory (which can't yet be tested) and hidden dimensions (which is to be tested by the Large Hadron Collider), and ends with the suggestion that the Scientific Methods fails when it comes to these bigger questions because of the very nature of those questiosn and the universe.

What are everyone's thoughts? Should we be searching for TOE? Is the scientific method incapable of providing TOE? What do you think TOE would actually be, whether it's proven or not?




And here's another article that suggests brain scans could be used to predict who is more likely to become a criminal and a threat to society, which could be used to imprison people for crimes they haven't committed or alternatively it could legally absolve people of responsibility for their actions and instead blame the brain abnormalities.

 

Even if you can never find it conclusively, it's still a good idea to keep searching for a TOE so we can develop models that better account for relativistic quantum mechanics. Approximations that are wanting are still superior to having no approximations at all.

On a somewhat-related note, I should point out that string theory and the notion of hidden dimensions are related, not separate approaches. As for string theory itself - no comment. I could hardly claim I'm an expert.

 

Freeman Dyson has stated that

? Gödel?s theorem implies that pure mathematics is inexhaustible. No matter how many problems we solve, there will always be other problems that cannot be solved within the existing rules. [...] Because of Gödel's theorem, physics is inexhaustible too. The laws of physics are a finite set of rules, and include the rules for doing mathematics, so that Gödel's theorem applies to them. ?
?NYRB, May 13, 2004


Stephen Hawking was originally a believer in the Theory of Everything but, after considering Gödel's Theorem, concluded that one was not obtainable.

? Some people will be very disappointed if there is not an ultimate theory, that can be formulated as a finite number of principles. I used to belong to that camp, but I have changed my mind. ?
?Gödel and the end of physics, July 20, 2002



Copied from Wikipedia.

I just wonder what we will be able to do with TOE. Will knowing what really lies under gravity help us in some practical way or just explain what we already know?

 

I agree that we should always keep trying to progress toward a better understanding of the universe, even if it's impossible to ever perfect our understanding of the universe.

Yeah, the article mentions them as related too, but I've seen other articles where scientists explore the possibilities of hidden "microscopic" dimensions even where it's not related to string theory. I really don't think we should be building theories on hidden dimensions until they are conclusively proven, and the article addresses this too but right now it looks like some scientists are inventing more dimensions just to make the universe fit into their theories instead of the other way around.

I've always had this strange, intuitive idea about the nature of the universe. Imagine a glass jar filled with sand. Something causes a single sand particle in the middle of the jar to start vibrating, and since the sand is all packed together then in order for that particle to vibrate/move then it must cause the particles around it to vibrate/move, setting off a chain reaction where many particles of sand in the jar are vibrating and moving around. Now imagine that glass jar is actually infinite in space, and you have the universe. The vibrating/moving bits of sand are matter&energy, and the majority of sand particle which are either still or "pass on the wave" of movement are empty space (which is why a substance can ever reach absolute zero). The initial action that started off the chain reaction was the Big Bang. I called it the Vibrotential Theory... yeah I was a weird little kid.

Well I think science-fiction fans like ourselves would hope a discovery of TOE would lead to technological manipulation of gravity, so we can finally have flying cars and tesseracts for space travel.

As for Gödel's Theorem, I don't think discovering TOE would mean there would be nothing left to learn. We would just have an overview and general understanding of how everything in the universe works, but not a complete understanding of all the special cases and odd combinations of those general rules that make the universe such an interesting and everchanging work in progress.

 

I'm going to have to disagree with your interpretation of the validity of hidden dimensions - the majority of the major physical breakthroughs of the past century have been predominantly seen in theoretical models first, and then experiments have later verified them. Hell, quite a few principles of quantum mechanics didn't have a solid experimental basis until 40+ years after they were first discovered (For example, and I'll freely admit I only know this because of a lab writeup I did last night, quantum entanglement is at least as old as the EPR paradox proposal in 1935, and wasn't verified experimentally until 1972). So yes, some physicists will object to the hidden dimension theory - Einstein thought quantum scale probability was outrageous, Schrodinger thought the Copenhagen interpretation was fundamentally absurd. By contrast, all I ask for is consistent theoretical frameworks.

Don't misconstrue this as an endorsement of hidden dimensions - I don't know enough about them to make a call either way - but I do object to the notion that theoretical physics is somehow "scientists inventing something to fit their theories." And of what I do know about multidimensional analysis, they are always tested for conformability with currently accepted physical models, and that such conversions can prove to be handy tools (All of classical electromagnetics can be reduced to two tensor equations in a four dimensional analysis. Two!). So it's a perfectly valid field of investigation.

On an unrelated note, a tesseract is just a four dimensional equivalent of a cube, it's got nothing to do with space travel. And no, I never did like A Wrinkle in Time.

 

Spacetime bending caused by spinning galaxies could explain why there's more matter than anti-matter?

The puzzling prevalence of matter over antimatter in the universe might be related to the bizarre space-time stretching caused by our galaxy's spin, a new study suggests.

Antimatter is a strange cousin to the stuff that makes up galaxies, stars and us. For every matter particle there is thought to exist an antimatter partner with the same mass but opposite charge. When matter and antimatter meet, they annihilate, converting their mass into energy in a powerful explosion.

Though the universe today is almost completely made of matter, scientists don't understand why. The Big Bang that created the cosmos 13.7 billion years ago should have produced equal parts matter and antimatter, which would have annihilated, leaving the universe barren of either. Luckily, it didn't (hence the Earth and the life it supports are here).

To what we owe our good fortune, physicists haven't much of an idea. But a new study that takes the spinning of our galaxy into account could point the way. [Wacky Physics: The Coolest Little Particles in Nature]

Physicist Mark Hadley of the University of Warwick in England calculated the effects of the Milky Way's spin on the space-time around it. According to the theory of general relativity, the speed and angular momentum of such a large spinning body twists the space and time around it in a process called frame-dragging.

Because of the mammoth mass of our galaxy, this twisting should have an impact on space-time that is more than a million times stronger than that of Earth's spin, Hadley found.

These changes to space and time ? in particular a stretching of time called time dilation ? could in turn affect how particles break down. Because of their different properties, matter and antimatter particles might react differently to the time dilation and decay at different rates because of it. [Video: Flying Space-time's Warps and Twists]

For some time, physicists have measured this asymmetry in decay rates between matter and antimatter, and called the phenomenon charge-parity violation (CP violation). But no one yet has a firm explanation for how the asymmetries came about.

"These [violations] have been measured but never explained," Hadley said in a statement. "This research suggests that the experimental results in our laboratories are a consequence of galactic rotation twisting our local space-time. If that is shown to be correct then nature would be fundamentally symmetric after all."

Hadley thinks that matter and antimatter aren't actually asymmetric at the root of things, but that their differing responses to the changes wrought by galactic rotation simply give this appearance. He says that if the overall big picture of all particles is taken into account, the variation of different levels of time stretching averages out and CP violation disappears.

"CP violation is seen as the key to explaining the matter asymmetry in the universe, but the measured CP violation is inadequate to explain the universe that we see today," Hadley wrote in a paper describing his findings published this month in the journal Europhysics Letters.

Instead of using CP violation to explain the prevalence of matter over antimatter in the universe, Hadley suggests that space-time warping may solve the mystery. Perhaps the spinning of massive structures formed early in the universe also stretched out time and space in a way that affected the overall distribution of matter and antimatter, he proposed.

To test his hypothesis, Hadley said researchers could investigate the findings of two experiments going on right now: the particle collisions produced inside the world's largest atom smasher, the Large Hadron Collider at CERN in Geneva, and the BaBar experiment at the SLAC particle physics laboratory at California's Stanford University, which studies CP violation in the decay of particl

 

Or, saying that mathematically, it'd work if you put the sun at the center instead of the earth?

 

Yeah, but where's the proof for the extraordinary claim that there are more than three spatial dimensions? They shouldn't be building models for how the universe works, saying their model needs 11 dimensions to work, without first saying why we should believe there are 11 dimensions. Either focus on proving/disproving the extra dimensions, or work on models that only include the dimensions that we know exist.

If this seems like a disconnect from my thoughts in the Atheism thread, it's because there's a difference between personal belief and Science. Science is supposed to be objective, based on proof and evidence, and overall held to a much higher standard.

It's like string theory. Yeah, it would be cool if everything was really made of the same microscopic strings/membranes, and the different sub-atomic particles exist because they vibrate differently. It's cool to wonder about. But where's the evidence?

Maybe the reason nothing can reach absolute zero is because when matter/energy reaches that temperature, it stills, and turns back into empty spacetime. That's a cool thing to wonder about. But where's the evidence?