off topic The Science Thread

[MattPie]

Are they coming back in that vehicle propelled by cold fusion?

 

The cold fusion part is just used to power the jump starter and A/C.

[WildCard]

Taking the scientific logistics of comics and cartoons and showing you how insane they are, this guy's youtube channel is awesome.

[LastPommerFan]

Ok, Physics people, I need two ideas explained to me better, because I'm having trouble, and I'm sure there are clearer explanations than the ones I've received:

 

1- The universe is expanding, but it has no boundary, so it's not expanding into anything.

 

2- There is no 'before the big bang' because time wasn't a thing until the big bang happened.

 

Much obliged,

 

Whiskey

[IKnowPhysics]

Ok, Physics people, I need two ideas explained to me better, because I'm having trouble, and I'm sure there are clearer explanations than the ones I've received:

 

1- The universe is expanding, but it has no boundary, so it's not expanding into anything.

 

2- There is no 'before the big bang' because time wasn't a thing until the big bang happened.

 

Much obliged,

 

Whiskey

 

 

I got you. Wiki is your friend on a lot of these sorts of topics, but some of the articles can be pretty thick and require a pretty good level of understanding.

 

1) Correct-ish.  The metric by which we measure spacial distance in the universe, an inherent property of the universe, is expanding.  Imagine a box, and in it is the universe with everything in it.  Incorrect thinking: the universe was previously small and in the middle of the box, then it exploded, and it is still expanding to take up more space in the box.  Correct thinking: when the box was made, the universe already took up the entirety of the box.  In a manner of speaking, we sort of measure distances in space by how far they are in fractions-of-boxes.  The distances we measure, because they rely on the size of the box, use a metric, which is an inherent property of the box.  But we've figured out that those fractions-of-a-box are getting bigger because the box is getting bigger.  And what you can't do is go outside the box and see what's there or how big the box is, because if you could, you'd still be inside the box.  The physics models only describe what's in the box and how the box works, not what does not and cannot exist outside the box. 

 

2) Correct. Instead of inventing an easy way to talk about this, I'll point you to Hawking, whom I think writes pretty accessibly about the subject:

 

 

The conclusion of this lecture is that the universe has not existed forever. Rather, the universe, and time itself, had a beginning in the Big Bang, about 15 billion years ago. The beginning of real time, would have been a singularity, at which the laws of physics would have broken down. Nevertheless, the way the universe began would have been determined by the laws of physics, if the universe satisfied the no boundary condition. This says that in the imaginary time direction, space-time is finite in extent, but doesn't have any boundary or edge. The predictions of the no boundary proposal seem to agree with observation. The no boundary hypothesis also predicts that the universe will eventually collapse again. However, the contracting phase, will not have the opposite arrow of time, to the expanding phase. So we will keep on getting older, and we won't return to our youth. Because time is not going to go backwards, I think I better stop now.

So, you can imagine what happens before the Big Bang, using our mental concept of time, but time doesn't really actually begin until our universe does, during the Big Bang.

 

A fun aside: particle colliders, like the Large Hadron Collider, make physics conditions of extremely high energies/temperatures.  The conditions are similar to the conditions that existed in the universe shortly after the Big Bang, as the universe cooled quickly.  By using colliders, we probe the physics of the Big Bang and learn about what types of particles and radiation existed back then.  The LHC has been able to make temperatures of ~10^17 degrees Kelvin (13TeV), which corresponds to the temperature that the universe was ~10^-14 seconds after the Big Bang (I could be off by a few orders of magnitude).  The higher in energy we go, the closer to the Big Bang we get to look.

 

And there's still a lot we don't know, like what dark energy and dark matter are and what it's up to or when and how it's all going to end.

[LastPommerFan]

Thanks IKP. I knew you wouldn't let me down!

Follow-up question:

 

A common argument against the possibility of FTL travel goes as follows:

 

1. The existence of intelligent life elsewhere in the Galaxy is essentially a statistical certainty.

2. We live on a very young star (4B years vs. 13B for the milky way)

3. If FTL travel were possible, we would have been contacted by an intelligent alien race with the capability for FTL travel.

... FTL travel is impossible.

 

Does this argument stand up? what are the counter arguments?

[Weave]

"We've" been contacted, but not during the period of written human history?

[IKnowPhysics]

Thanks IKP. I knew you wouldn't let me down!

Follow-up question:

 

A common argument against the possibility of FTL travel goes as follows:

 

1. The existence of intelligent life elsewhere in the Galaxy is essentially a statistical certainty.

2. We live on a very young star (4B years vs. 13B for the milky way)

3. If FTL travel were possible, we would have been contacted by an intelligent alien race with the capability for FTL travel.

... FTL travel is impossible.

 

Does this argument stand up? what are the counter arguments?

 

Not really.  None of those statements is really bulletproof, and the attempted logical extension that faster than light travel is impossible falls flat.  There's similar arguments that say that time travel must be impossible, relying only on the argument that we haven't met a time traveler yet (despite some weak efforts).  There's also logical similarity to Roko's Basilisk (warning: you may be tortured by an evil supercomputer).

 

The uniqueness that is our form of intelligent species is a product of the physics of our temperature/energy domain, the exacting evolution of our local cosmos, the incredibly specific chemistry and resulting biochemistry of our planet, the hundreds of millions of years of species evolution, the thousand years of mathematical and scientific enlightenment, and the hundred years of aerospace endeavor.  We're currently the only known species that has the intelligence, resources, and gravity conditions to attempt space flight and is also interested in attempting space flight.

 

Even if we were being contacted or visited, we may not even know what we're looking for or at.  Even reducing our search for intelligence to something comprehensible on our own spatial scale (>0.01mm to <10km) or looking for signs of existence or communication that we could even remotely begin to detect and understand could be limiting the search to narrowly.

 

But there are a lot of planets and there has been and still is a lot of time.

 

As for travel speeds, our current physics models show matter and energy as we know it topping out at light speeds. Is it possible to break beyond that?  No, not without adjusting the model.  And in all likelihood, we're talking about an incalculable amount of energy required to achieve this, without getting into wormholes and other space-time oddities.

 

Does this kill the chances for interplanetary and interstellar human travel?  Naw.  Time dilation is probably the single biggest aid to us for long-distance travel. The faster the spacecraft goes, the "faster time goes" on the spacecraft.  For instance, for constant acceleration and then deceleration at 1g, to reach the center of the galaxy (30,000 light years away), the time experienced on the spacecraft would only be 20 years.  We would just need the energy to accelerate and decelerate a spacecraft like that.

[bunomatic]

Thanks IKP. I knew you wouldn't let me down!

Follow-up question:

 

A common argument against the possibility of FTL travel goes as follows:

 

1. The existence of intelligent life elsewhere in the Galaxy is essentially a statistical certainty.

2. We live on a very young star (4B years vs. 13B for the milky way)

3. If FTL travel were possible, we would have been contacted by an intelligent alien race with the capability for FTL travel.

... FTL travel is impossible.

 

Does this argument stand up? what are the counter arguments?

They have been here in the past and are still here. The evidence is all around us. Every creation myth, folklore from almost every corner of the earth, myths, cave paintings , architecture(pyramids) , religions , etc. Too many examples to list. Disclosure officially began a few years ago and will continue over the next 10 years or so to slowly break us in to the big not so secret secret. Scoff at your own peril. The truth is out there.

[LastPommerFan]

Not really. None of those statements is really bulletproof, and the attempted logical extension that faster than light travel is impossible falls flat. There's similar arguments that say that time travel must be impossible, relying only on the argument that we haven't met a time traveler yet (despite some weak efforts). There's also logical similarity to Roko's Basilisk (warning: you may be tortured by an evil supercomputer).

 

The uniqueness that is our form of intelligent species is a product of the physics of our temperature/energy domain, the exacting evolution of our local cosmos, the incredibly specific chemistry and resulting biochemistry of our planet, the hundreds of millions of years of species evolution, the thousand years of mathematical and scientific enlightenment, and the hundred years of aerospace endeavor. We're currently the only known species that has the intelligence, resources, and gravity conditions to attempt space flight and is also interested in attempting space flight.

 

Even if we were being contacted or visited, we may not even know what we're looking for or at. Even reducing our search for intelligence to something comprehensible on our own spatial scale (>0.01mm to <10km) or looking for signs of existence or communication that we could even remotely begin to detect and understand could be limiting the search to narrowly.

 

But there are a lot of planets and there has been and still is a lot of time.

 

As for travel speeds, our current physics models show matter and energy as we know it topping out at light speeds. Is it possible to break beyond that? No, not without adjusting the model. And in all likelihood, we're talking about an incalculable amount of energy required to achieve this, without getting into wormholes and other space-time oddities.

 

Does this kill the chances for interplanetary and interstellar human travel? Naw. Time dilation is probably the single biggest aid to us for long-distance travel. The faster the spacecraft goes, the "faster time goes" on the spacecraft. For instance, for constant acceleration and then deceleration at 1g, to reach the center of the galaxy (30,000 light years away), the time experienced on the spacecraft would only be 20 years. We would just need the energy to accelerate and decelerate a spacecraft like that.

Statement #2 is correct, right? Our star is one of the younger of the Galaxy. It's possible that I'm conflating Galaxy age with star age, when they are separate things.

[Randall Flagg]

Statement #2 is correct, right? Our star is one of the younger of the Galaxy. It's possible that I'm conflating Galaxy age with star age, when they are separate things.

I don't have time to check the numbers exactly but our star is definitely at least a 2nd/3rd generation star in our Galaxy, because the elements that make us up are too heavy to have been there during the lifetimes of the first wave of stars here.

[LGR4GM]

Not really.  None of those statements is really bulletproof, and the attempted logical extension that faster than light travel is impossible falls flat.  There's similar arguments that say that time travel must be impossible, relying only on the argument that we haven't met a time traveler yet (despite some weak efforts).  There's also logical similarity to Roko's Basilisk (warning: you may be tortured by an evil supercomputer).

 

The uniqueness that is our form of intelligent species is a product of the physics of our temperature/energy domain, the exacting evolution of our local cosmos, the incredibly specific chemistry and resulting biochemistry of our planet, the hundreds of millions of years of species evolution, the thousand years of mathematical and scientific enlightenment, and the hundred years of aerospace endeavor.  We're currently the only known species that has the intelligence, resources, and gravity conditions to attempt space flight and is also interested in attempting space flight.

 

Even if we were being contacted or visited, we may not even know what we're looking for or at.  Even reducing our search for intelligence to something comprehensible on our own spatial scale (>0.01mm to <10km) or looking for signs of existence or communication that we could even remotely begin to detect and understand could be limiting the search to narrowly.

 

But there are a lot of planets and there has been and still is a lot of time.

 

As for travel speeds, our current physics models show matter and energy as we know it topping out at light speeds. Is it possible to break beyond that?  No, not without adjusting the model.  And in all likelihood, we're talking about an incalculable amount of energy required to achieve this, without getting into wormholes and other space-time oddities.

 

Does this kill the chances for interplanetary and interstellar human travel?  Naw.  Time dilation is probably the single biggest aid to us for long-distance travel. The faster the spacecraft goes, the "faster time goes" on the spacecraft.  For instance, for constant acceleration and then deceleration at 1g, to reach the center of the galaxy (30,000 light years away), the time experienced on the spacecraft would only be 20 years.  We would just need the energy to accelerate and decelerate a spacecraft like that.

Isn't there a theory also that space itself is more like book.  Sure you could read (travel) from page 1-100 by reading every page in-between but you should theoretically be able to drill straight down through those pages to get to 100 without reading them aka a worm hole?

[IKnowPhysics]

Statement #2 is correct, right? Our star is one of the younger of the Galaxy. It's possible that I'm conflating Galaxy age with star age, when they are separate things.

 

Yeah, that's correct.  The Milky Way Galaxy had a high rate of star production around 10 billion years ago; our sun is only 5 billion years old.

 

I don't have time to check the numbers exactly but our star is definitely at least a 2nd/3rd generation star in our Galaxy, because the elements that make us up are too heavy to have been there during the lifetimes of the first wave of stars here.

 

Not sure this is the completely accurate.  The Sun's definitely a late bloomer in our galaxy and its age was determined by nucleocosmochronology (word of the day), but I'm struggling to accept that it was because of an especially high content of heavy isotopes (the method examines Uranaium and Thorium concentrations, but doesn't necessitate that the concentrations are especially high).  Due to the well-understood r-process and s-process, those higher concentrations of heavy elements usually appear in larger stars than the Sun (the Sun is a yellow dwarf, aka a G-type main sequence star).

[IKnowPhysics]

Isn't there a theory also that space itself is more like book.  Sure you could read (travel) from page 1-100 by reading every page in-between but you should theoretically be able to drill straight down through those pages to get to 100 without reading them aka a worm hole?

 

Not scientifical:

 

I like to think of space time like a piece of paper, or better, a piece of saran wrap.  It stretches a little when you put heavy things on it.  Generally, you can only move around on the surface.  But with enough energy, or something, you can fold it, and leap from one surface to another.

 

https://www.youtube.com/watch?v=n6lDG-bP3zg

 

http://www.youtube.com/watch?v=3cehwiHIlho

[TrueBlueGED]

Event Horizon was great.

[IKnowPhysics]

Event Horizon was great.

 

I liked it.  One of the last watchable space-related scifi horror films, excepting the enjoyable Prometheus.  Other recent films, like Pandorum, don't quite hold up.

 

FISHBURNE... IN... SPACE!

[shrader]

I liked it.  One of the last watchable space-related scifi horror films, excepting the enjoyable Prometheus.  Other recent films, like Pandorum, don't quite hold up.

 

FISHBURNE... IN... SPACE!

 

What, no Jason X?

[Sabre Dance]

They have been here in the past and are still here. The evidence is all around us. Every creation myth, folklore from almost every corner of the earth, myths, cave paintings , architecture(pyramids) , religions , etc. Too many examples to list. Disclosure officially began a few years ago and will continue over the next 10 years or so to slowly break us in to the big not so secret secret. Scoff at your own peril. The truth is out there.

Hmm...I've always thought that if a culture was intelligent enough to create faster-than-light travel, they'd also be smart enough to stay out of sight and observe the human race, but not interfere. (the "Prime Directive" as it were).  No, I think all the visitations we credit to extraterrestrials are actually our descendants travelling back in time to "fix" issues they imagine may need fixing.  (If we can postulate faster-than-light travel, time travel shouldn't be all that much of a stretch.)  We as humans just can't resist messing with things that we just shouldn't be messing with, even our future selves...

 

...oh, and Bigfoot and the Loch Ness monster did live in the past, but appear occasionally through a warp in the fabric of time.  That's why they're not there when people go looking for them.

[ubkev]

Hmm...I've always thought that if a culture was intelligent enough to create faster-than-light travel, they'd also be smart enough to stay out of sight and observe the human race, but not interfere. (the "Prime Directive" as it were).

I'm with you and Bill Hicks on this one. You'd think if they were to show up, they'd have the good sense to not choose Fyffe Alabama, like some intergalactic Joad family.

[bunomatic]

Hmm...I've always thought that if a culture was intelligent enough to create faster-than-light travel, they'd also be smart enough to stay out of sight and observe the human race, but not interfere. (the "Prime Directive" as it were).  No, I think all the visitations we credit to extraterrestrials are actually our descendants travelling back in time to "fix" issues they imagine may need fixing.  (If we can postulate faster-than-light travel, time travel shouldn't be all that much of a stretch.)  We as humans just can't resist messing with things that we just shouldn't be messing with, even our future selves...

 

...oh, and Bigfoot and the Loch Ness monster did live in the past, but appear occasionally through a warp in the fabric of time.  That's why they're not there when people go looking for them.

Aliens of the well travelled variety , time travel , inter dimensional , with a load of earth gov't black project stuff thrown in. Its all out there. You can bet that a false flag attack by aliens staged by earth gov'ts has been thrown around. I'm not sure it'll happen but that would really grab peoples attention and certainly turn them against the idea of compassionate visitors.

[MattPie]

I got you. Wiki is your friend on a lot of these sorts of topics, but some of the articles can be pretty thick and require a pretty good level of understanding.

 

1) Correct-ish.  The metric by which we measure spacial distance in the universe, an inherent property of the universe, is expanding.  Imagine a box, and in it is the universe with everything in it.  Incorrect thinking: the universe was previously small and in the middle of the box, then it exploded, and it is still expanding to take up more space in the box.  Correct thinking: when the box was made, the universe already took up the entirety of the box.  In a manner of speaking, we sort of measure distances in space by how far they are in fractions-of-boxes.  The distances we measure, because they rely on the size of the box, use a metric, which is an inherent property of the box.  But we've figured out that those fractions-of-a-box are getting bigger because the box is getting bigger.  And what you can't do is go outside the box and see what's there or how big the box is, because if you could, you'd still be inside the box.  The physics models only describe what's in the box and how the box works, not what does not and cannot exist outside the box. 

 

2) Correct. Instead of inventing an easy way to talk about this, I'll point you to Hawking, whom I think writes pretty accessibly about the subject:

 

 

So, you can imagine what happens before the Big Bang, using our mental concept of time, but time doesn't really actually begin until our universe does, during the Big Bang.

 

A fun aside: particle colliders, like the Large Hadron Collider, make physics conditions of extremely high energies/temperatures.  The conditions are similar to the conditions that existed in the universe shortly after the Big Bang, as the universe cooled quickly.  By using colliders, we probe the physics of the Big Bang and learn about what types of particles and radiation existed back then.  The LHC has been able to make temperatures of ~10^17 degrees Kelvin (13TeV), which corresponds to the temperature that the universe was ~10^-14 seconds after the Big Bang (I could be off by a few orders of magnitude).  The higher in energy we go, the closer to the Big Bang we get to look.

 

And there's still a lot we don't know, like what dark energy and dark matter are and what it's up to or when and how it's all going to end.

 

No particular comment, other than I love these high-level physics posts from the poster with someone chugging a beer as an avatar. Thanks for the chuckle.

[Taro T]

Just because this is the "science" thread, thought this would be an interesting article.

 

It was posted over on the TBD PPP board which most here won't touch w/ a 10 ft pole.

 

http://fivethirtyeight.com/features/science-isnt-broken/

 

Reminds me of the mantra that was drilled into our heads by 1 of the best undergrad profs I had. Don't trust that the authors &/or peer reviewers didn't make any errors. Review the work (and if at all possible the data) yourself before blindly accepting what you read. Trust but verify. It's what makes science such a powerful tool.

[LGR4GM]

http://news.sciencemag.org/physics/2015/08/secretive-fusion-company-makes-reactor-breakthrough

"In a suburban industrial park south of Los Angeles, researchers have taken a significant step toward mastering nuclear fusion—a process that could provide abundant, cheap, and clean energy. A privately funded company called Tri Alpha Energy has built a machine that forms a ball of superheated gas—at about 10 million degrees Celsius—and holds it steady for 5 milliseconds without decaying away. That may seem a mere blink of an eye, but it is far longer than other efforts with the technique and shows for the first time that it is possible to hold the gas in a steady state—the researchers stopped only when their machine ran out of juice."

[IKnowPhysics]

The takeaway from that article isn't that anyone's close to an economical commercial fusion plant, but rather that a decent number of small-to-medium scale experiments at private firms are taking on the challenges of magnetically confined fusion empirically with iterative and inexpensive approaches, despite lacking simulation and modeling capability to correlate their findings to theory.

 

Also, I've met the only scientist in that article that doesn't have a stake in those companies.

 

Still do be wary about science that goes right out to press instead of peer-reviewed journals.

[WildCard]

Event Horizon was great.

One of my favorite movies, even though it terrifies the hell out of me.

 

I liked it.  One of the last watchable space-related scifi horror films, excepting the enjoyable Prometheus.  Other recent films, like Pandorum, don't quite hold up.

 

FISHBURNE... IN... SPACE!

Not a fan of Prometheus. I was looking for something more of our origins then what instead they tied it in with,

 

 

Speaking of space. We're going to Mars, ######! If they fund NASA (about $75 billion dollars, or about 12% of our annual military spending) and you live to see 2040 or so. 

http://www.space.com/29562-nasa-manned-mars-mission-phobos.html

Edited September 22, 2015 by WildCard

[WildCard]

Gonna make this brief, but if you have more questions I would love to answer them. Intel can no longer keep up with Moore's Law; within the next decade they know they will ultimately fail the famous model that is one of the largest reasons for computer innovation in the last 50 years. So, what do they do? They'll try another manner of transistors, but it is physically impossible, because eventually the heat will melt the chip.

 

So, what are we left with. QUANTUM COMPUTERS. Learn it, love it, live it. These babies will be the next age of computing. They will be the next age of science. They will be the most important breakthrough since microprocessors or transistors. And, guess what? They're well on their way.

 

 

 D-Wave Systems Inc., the world's first quantum computing company, today announced that it has broken the 1000 qubit barrier, developing a processor about double the size of D-Wave’s previous generation and far exceeding the number of qubits ever developed by D-Wave or any other quantum effort.  This is a major technological and scientific achievement that will allow significantly more complex computational problems to be solved than was possible on any previous quantum computer.

 

 At 1000 qubits, the new processor considers 21000 possibilities simultaneously, a search space which dwarfs the 2512 possibilities available to the 512-qubit D-Wave Two. ‪In fact, the new search space contains far more possibilities than there are ‪particles in the observable universe.

http://www.dwavesys.com/press-releases/d-wave-systems-breaks-1000-qubit-quantum-computing-barrier

I mean....just think about it guys. It's beautiful what these things can do. And we'll be alive for it! Our kids won't know how life was before them. Well, maybe not, because they probably won't be personalized like that. But, science! Science guys, science is going to cry for these things. So, so much data, more than we can even comprehend, can be processed in under a second. Space travel, elections, health studies, best-possible scenarios, SPACE. God I can't wait