SETI make's alien contact?

[DefragMyHead]

I always thought it was arrogant when I heard a scientist say something like, "well, we know of a few basic things you need for life to exist, water and oxygen for instance." And Im all like, who the **** are you? There could be something methane drinking, carbon monoxide breathing sentience somewhere! Of course I have nothing at all to back my fantasy theory up, but the point is still solid: we gots lots to learn, and current LAWS are not concrete. Not ever, not in anything.

 

[Apokalipse]

Spin up the FTL drive, we're about to make a faster-than-light jump.

I hope you don't mean literally "faster than light"
because as einstein's relativity tells us, nothing can pass the speed of light, or even travel at the speed of light for that matter (except light itself, it always has a constant speed no matter what).

 

[Spartan]

I hope you don't mean literally "faster than light"
because as einstein's relativity tells us, nothing can pass the speed of light, or even travel at the speed of light for that matter (except light itself, it always has a constant speed no matter what).

http://www.scienceblog.com/light.html

Interesting read. According to einstein, objects can't travel at the speed of light, because this takes infinite energy and in turn, infinite mass. However, light can be controlled to go faster or much slower than the speed of light.

 

[molsen]

on topic, SETI did not make alien contact. this is some crap made up by some conspiracy type.... did you see the website from which this news originated? crap crap crap

""but that now they are getting external human, probably NRO or NSA jamming of those signals and they are getting very frustrated. ""

this is typical conspiracy theory drama. they add this kind of stuff so people don't ask smart questions like "why isn't SETI reporting this on their website?" "why isn't this news reported ANYWHERE ELSE?" oh because the gov't doesn't want you to know.

i believe in ET's, but this news is crap

oh and for those of you naysayers about interstellar space travel, consider this:

--we used to think the sound barrier was impassible. (more specifically, theoretical work "indicated the pressures generated on a body as it neared Mach 1 would go to infinity, and the drag would therefore be so great that no aircraft could pass through the barrier") sound familiar? the mass of any object approaching the speed of light approaches infinity?

--we used to think the world was flat and that you could sail off the edge.

but knowledge was acquired and we passed those barriers. just because our current knowledge doesn't allow for interstellar travel, doesn't mean it's impossible. it's just impossible RIGHT NOW.

also, life is possible in many different environments other than our own. you know there are organisms that live right around volcanic vents at the bottom of deep ocean trenches. the water is mixed with some sort of sulfide and methane to create a high pressure, high temperature goo with the consistency and toxicity of drano, but yet there is life.

to many closed minds in this thread

 

[Waphlez]

Yea, Einstein's Theory of Relativily is very intresting. Before people thought time was constant and light was relative, but it's the opposite. It's weird that time actually slows down the faster you move. They proved this when they had two identical super clocks synced to like the ten-thousanth second, one was on a plane another was on the ground and the plane clock was actually slower then the ground clock.

Another thing I thought about was let's say that you were traving at the speed of light and if you look in the opposite direction of where your moving wouldn't the image you see will be the exact same and never will change? And if you're moving faster then the speed of light would you see nothing but black (since light can't keep up with you)?

 

[Apokalipse]

this is what Einstein came up with, and so far it has proved accurate:

M = M0 x [1 / sqrt(1 - V²/C²)]

M is the mass of an object travelling at a velocity of V m/s

M0 is mass of the same object at rest

V is the velocity in m/s

C is the speed of light (3 x 10^8 m/s)

now, the bigger V gets, the lower the value of (1 - V²/C²) will get.

if V was, let's say, 2 x 10^8, then:
1 - (2 x 10^8)/(3 x 10^8) = 1/3
1 / sqrt(1/3) = sqrt(3)
at a velocity of 2 x 10^8, an objects mass will be sqrt(3) times their normal mass.

when V reaches the speed of light (3 x 10^8 m/s) then:
1 - (3 x 10^8)/(3 x 10^8) = 1-1 = 0
sqrt(0) = 0
and 1/0 is undefined.

 

[magouster]

I might have misunderstood Einstein, because I was sure that Relativity says nothing can accelerate faster than the speed of light, and NOT travel faster than light.

Logically, if you inreased your speed at a rate of a millionth of a mile an hour, until you reach the speed of light, why would mass or energy have anything to do with it? Mass only affects acceleration, not speed.

This is all theoretical anyway, because we don't have an energy source efficient enough to keep accelerating until we reach the speed of light. Arthur C. Clark wrote about spaceships with "sails" of a very light material, that could be used to capture particles emited from the sun like a ship uses sails to capture wind, to propel Science fiction - I know - but old Arthur had some pretty wicked ideas, some of which weren't so far from reality today.

 

[Apokalipse]

in order for something to move, it must accelerate. you can't just make something instantly travel at a certain speed.

Ek = (1/2)mv²
where Ek is kinetic energy of an object
m is the mass of the object
v is the =velocity of the object

when something moves, it has kinetic energy depending on its mass and velocity.

because of conservation of energy, you cannot pull energy out of nowhere. you must convert energy from one form into kinetic energy. this energy has to exert a force on the object for it to move.
the amount of force you need to accelerate at a constant acceleration is f=ma

where f is the force (in newtons)
m is the mass of the object (in kg)
a is the acceleration (in m/s)

also, when you apply einstein's relativity, the further you increase your velocity, the more mass the object has. and the more force you need to accelerate the object at a constant acceleration. when you approch the speed of light, it increases asypmtotically, such that at the speed of light, it would be infinite also (since f = ma, ans mass is infinite at the speed of light)

 

[magouster]

Relativity fails under certain circumstances though. Take light itself. It has been shown that light exists both in a wave-form, as well as a particle-form. Light has mass, since it can be bent around bodies with immense weight, and even be completely stopped (as is the case of the event-horizon of a black hole - yes, I know black holes only exist in theory). So how can it travel at the speed of light?

 

[Apokalipse]

I realised I made a mistake (four posts up). I forgot to square V and C.
but anyway, the result doesn't change when V = the speed of light.

to answer your post:
Einstein postulated that gravity is not the physical attraction of matter.
it is the curving of space-time in the prescence of matter.

where any object of X mass exists, space-time curves a certain amount. the amount it curves is proportional to the objects mass.
(gravity is usually calculated using F = GM/R², where F is the force in Newtons, G is a constant, M is the mass of the object in kg, R is the radius in metres)

anyway, if we have anything travelling in a straight line, and then it finds its way onto curved space-time, the object does actually travel straight relative to space-time. but since space-time is curved, the objects path as we see it, curves

this explains why light is also subject to gravity.
in a black hole, the light is not stopped. it is just curved to such an extent, that it doesn't travel out of the black hole.

at the precise location of the event horizon, there is often light orbiting the black hole.

a = V²/R, for any object in a circular orbit around a central point.
a is the acceleration towards the centre
V is the velicoty
R is the radius from the centre

we can apply this to the event horizon and light:
V would be the speed of light, and a would be the acceleration towards the centre of the black hole.
depending on how much force the black hole exerts, R would be the exact radius of light's orbit around the black hole, and also the exact radius of the event horizon.