Cosmos-a space-time odyssey

[uberevan]

Einstein believed in the Tachyon particle, and that you could latch onto them and travel faster than light.  If he were right about that we wouldn't have these problems, but a Tachyon has yet to be found.  Though I hear they've found plenty of evidence for the Higgs Boson recently, which was also considered a myth so you never know.

Of course, how would we even latch onto them, or let go once we make it?

Another way proposed to move FTL is to bend the space in front of you to accelerate forwards faster than light could travel under normal conditions.

[Rathlord]

 but I did find a cool article on a "Tachyonic antitelephone", which could make calls into the past. 

 

Which leads me to the question, if I order a pizza an hour in the future, do I get it free?

 

This was posited by both Einstein and Arnold Sommerfield. Believe it or not, the first time I read about Tachyon particles I actually came up with the same theory as they did before ever hearing about it, and then on recent found that my theory was logically sound. Was fairly proud of myself that day.

 

Tachyons and other faster-than-light particles only make sense if you posit that they can slip in and out of extra dimensions (and would probably still be traveling actually slower than light, but crossing the distance from point A to point B faster than light would, making it relatively faster than light. As has been said, there's no evidence to support that any such thing exists in our current understanding of existence, but there certainly could be someday.

[uberevan]

Tachyons and other faster-than-light particles only make sense if you posit that they can slip in and out of extra dimensions (and would probably still be traveling actually slower than light, but crossing the distance from point A to point B faster than light would, making it relatively faster than light. As has been said, there's no evidence to support that any such thing exists in our current understanding of existence, but there certainly could be someday.

That's kind of the bend space theory I was referring to, though not exactly what I meant.  Like a wrinkle in time-space almost...

[Rathlord]

The way I like to think of it in a very general sense, is that it's like dropping a baseball off of a tall building- after a certain amount of time, due to the pull of gravity and wind resistance, it hits terminal velocity (in our example, the speed of light). The baseball would be a  typical photon. But for a tachyon, it'd be like a baseball that didn't have any wind resistance. As if it was still falling, but it didn't exist entirely in our dimension so it just went right through air rather than push it aside, thus going faster than terminal velocity (aka speed of light).

[mikaelkerensky]

In theory current ion drive engines could exceed the speed of light with the amount of time to build up speed being the only factor. That said, once past the speed of light how do you communicate with the engine to slow it down? Would it just explode or would it enter something akin to hyperspace. If we lost communication with such an engine how would you even get info on what happens to it?

[Kirrus]

No  -- the speed of light is the universe's hard speed limit, as far as we can tell no matter can go faster than it, not even with a mahoosive engine. Now, theoretically, we can get to a fraction of the speed of light more easily now, but not actually go faster than it.  It's why science fiction always has some type of magic to go faster than the speed of light, and why that type of travel is called FTL -- Faster Than Light.

 

That's why current theories range on bending spacetime itself, to using wormholes to cheat around the limit.

[mikaelkerensky]

But according to current tech (re:ion engines) the power required is extraordinarily low, and the speed of the engine increases exponentially. At some point the exponential curve exceeds speed of light. My question pertains to what happens to said engine close to the speed of light. Does it self destruct? Does it hit light speed and not increase speed further (due to lack of power from photons not catching up and powering the device), or does it actually finally exceed the speed of light. And even then, since information to deep space probes is transmitted, at maximum, the speed of light, do we lose communications and get no further info from it?

[Nickenstein79]

 

But according to current tech (re:ion engines) the power required is extraordinarily low, and the speed of the engine increases exponentially. At some point the exponential curve exceeds speed of light.

 

 

 

No, no, no.

 

Mass and energy are two sides of the same coin. To accelerate an object with _any_ mass to the speed of light requires infinite energy.

 

Another way to look at it: An object's mass ('m') approaches infinite as it's speed (energy 'e') approaches the speed of light ('c').

 

E=mc2  ->  m = e/c²

[Kirrus]

 

 

But according to current tech (re:ion engines) the power required is extraordinarily low, and the speed of the engine increases exponentially.

 

 

 

No, no, no.

 

Mass and energy are two sides of the same coin. To accelerate an object with _any_ mass to the speed of light requires infinite energy.

 

Another way to look at it: An object's mass ('m') approaches infinite as it's speed (energy 'e') approaches the speed of light ('c').

 

E=mc2  ->  m = e/c²

 

 

Totally what Nick said, but to put it really insanely simply, the faster you go, the heavier you are. Ion engines *are* efficient -- they can get you faster on less fuel (in no atmosphere), but they're not magic, they still can only push you so fast, and no faster

[mikaelkerensky]

That's assuming Einstein was right about the theory of relativity. even he spent his latter years trying to prove the theory of relativity wrong because he felt something was off about it. With the current dichotomy between quantum physics and large scale phenomena, until we achieve a grand unified theory i think current physics can't be the correct approach. Something is missing.

[Kirrus]

It's the best we have now, and all our tests match it. Remember, we've got space probes actually using ion engines, and they're not that great, we already know their limitations.

http://en.wikipedia.org/wiki/Deep_Space_1

 

There may be a loophole in the relativity theory, but no-one's found it yet. Feel free to become an theoretical physicist and try and work it out!

[mikaelkerensky]

Believe me i want to! Just can't survive on the pay.

[Nickenstein79]

 

That's assuming Einstein was right about the theory of relativity. even he spent his latter years trying to prove the theory of relativity wrong because he felt something was off about it. 

 

He didn't like the cosmological constant in his 'general' theory of relativity (a theory mostly concerned with gravitation). It felt like a fudge in the maths to him. It has since been shown that the anti-gravitational effects of dark energy account for this constant. So he was not wrong, he just didn't know about the existence of dark energy. (That is to say, he didn't know why he was correct.)

 

However, we are actually talking 'special' relativity here.

 

All modern communications would collapse if it were wrong. For one, GPS is completely reliant on the time dilation effects predicted by special relativity.

 

EDIT: What we are really talking about here is mass-energy-equivalence (e=mc2), which is intertwined in both general and special relativity, and is very heavily backed up and confirmed by pretty much everything in known physics.

[Rathlord]

There's a nifty theory on a warp drive that's plausible if you had enough antimatter posed by that brilliant oriental looking theoretical physicist whose name I can't recall. Michael something? Previously it needed a planet sized amount of antimatter, but he's come up with a more efficient design since that would take much less.

[Nickenstein79]

There's a nifty theory on a warp drive that's plausible if you had enough antimatter.

 

 

I saw a documentary about a bloke who had one of those. He had a strange hair-grip over his eyes.

[Rathlord]

XD

There's a name for what ion engines do in math- it's not true exponential growth. I can't seem to recall it at the moment, though. It approaches speed of light but could never eclipse or reach it.

Also, things wouldn't be destroyed just for passing the speed of light in theory. The forces might tear it apart, but it wouldn't just implode. And no, as long as it continued at that speed no external communication could reach it- though internal communications would work fine.

[mikaelkerensky]

There's a nifty theory on a warp drive that's plausible if you had enough antimatter posed by that brilliant oriental looking theoretical physicist whose name I can't recall. Michael something? Previously it needed a planet sized amount of antimatter, but he's come up with a more efficient design since that would take much less.

Michio Kaku?

[Rathlord]

That's the one. That man is my idol- got a few of his books sitting around my flat. They're good reads, and he communicates excellently for a man of his intellect and field.

Edit: Fixed your quote for you.

Only problem with his warp drive is that if you arrived at a planet, the forces used to transport you would annihilate it. Might have to park in the back.

[mikaelkerensky]

Michio Kaku and Neil deGrasse Tyson are my heroes in astronomy and cosmology. We need more scientists like them. So eloquent and knowledgable...

[Kirrus]

Only problem with his warp drive is that if you arrived at a planet, the forces used to transport you would annihilate it. Might have to park in the back.

On the plus side, if anyone else actually does travel doing that, we should be able to spot them from here

[Rathlord]

Fair point XD

[Nickenstein79]

Michio Kaku and Neil deGrasse Tyson are my heroes in astronomy and cosmology. We need more scientists like them. So eloquent and knowledgable...

 

Agreed. They are both super awesome. However, what we actually need is much more TV-time dedicated to actual science, not celebrities. Like it used to be in the 80's, with scientists actually explaining things properly, rather than half-explanations followed by wizzy graphics.

 

That kind of TV could have stopped you yourself from conflating special relativity with general relativity and mass-energy-equivalence, as you have done in your comments above.

 

The trend these days seems to be "Actual science is hard, so let's focus on graphics and hopefully sneek a few half-facts into the viewer's brain whilst they look at the colours!"

 

This is why the recordings of university lectures given by Krauss/Kaku/Tyson should be played on prime-time-TV. Not the the dumbed-down shows made-for-TV, but the *actual* university lectures.

 

I _really_ miss the old BBC-Open-University shows. :'(

[Rathlord]

The trend these days seems to be "Actual science is hard, so let's focus on graphics and hopefully sneek a few half-facts into the viewer's brain whilst they look at the colours!"

 

 

Unfortunately it's not even that- it's just that science doesn't sell. People are stupid, and wish to remain that way, and they don't want anything to do with science that isn't sparkly graphics and excitement. I, too, would love to see more meaty programming, but it just isn't a tenable way to do business for the networks.

[Nickenstein79]

That's my main gripe here. In the olden days (with BBC-Open-Universty), the BBC stuck to their remit of public education based on it being publicly funded. BBC-1 had popular-entertainment and news, BBC-2 had niche entertainment and education (so you had OU-physics lecture/SkyAtNight at various rare times. Now that is all gone.)  

 

The best things in that same style are now only found on YouTube (not on mainstream TV like they used to be, AND SHOULD STILL BE!).

 

My two favourites are:

 

1: (already mentioned by CaptainBinky)

Lawrence Krauss - A universe from nothing lecture.

 

2: Leonard Susskind: an entire set of lectures on theoretical physics given at Stanford university (this is a full set, this constitutes all of the info given to students studying theoretical physics at Stanford, from a world renowned physicist! Drink it in! Suck up this very expensive education for free! All of the parent's of the students in that class here payed a fucking fortune for this tutelage! HAVE IT! Also, if you know matrix maths before watching, this is all surprisingly easy to absorb!)

https://www.youtube.com/playlist?list=PLQrxduI9Pds1fm91Dmn8x1lo-O_kpZGk8

[CylonBookworm]

I haven't been keeping up with the show, but from the 2-3 episodes that I've seen I... I dunno. Tyson is pretty good. The effects aren't half bad. The comic bit is a bit weird. The one thing I don't like is the whole pro-atheist tilt to the whole show. I mean c'mon, Carl Sagan never pushed his beliefs on anybody. He offered up science and facts and let people choose their own beliefs, make their own conclusions and opinions. He didn't judge anybody for their beliefs, and he was open to the idea that he could be wrong. This new Cosmos with Tyson just spouts the old Atheist line every damn episode, which is why I haven't been keeping current. I'll go back to Carl Sagan's books, and the REAL "Cosmos" on Netflix, and the Sagan series on youtube.