Carl Sagan on looking out into space = back into time

[1billion1deaths1]

LIGHT IS EVERYTHING,Sound ,memories, thoughts are light , Extraterrestrial elements.

[masroorabbas]

@JP5466 Amazing isnt it in in 1980 I was not even born...in fact I was born 6 years after that and today we both are watching this awesome video!!!!!lol

[KayBeeEee1983]

Speaking of going back in time, when's the turtleneck & sportcoat combo gonna make a comeback?

[isaacisblackmagic]

i wanted to keep on watching lol :(

[snookerjam]

i just recently discover this wonderful scientist, its absolutely great listen to him and also his voice make me calm and focused to his messages. he was a very very bright and intelligent man

[WOWJBEOWULF]

The Universe is infinite. If the Universe were finite, we would be like a hot cup of coffee, heated to the energy of the stars (like putting an airconditioner in the bottom of a mine, there is no place to pump the heat energy, it does nothing except have a hot side and cold side on the heat pump). The only explanation left is the Universe is infinite (i.e. very large). Heisenberg's Uncertainty Principle states nothing is impossible, as momentum & position is known, thus infinite Creation.

[opiates]

That looks a lot like constellation Lyra in the beginning.

[camboishawt]

well spoken but it doesnt enhance your mind pot just opens another part and closes other parts that would other wise be utalized when sober your looking through the attic window cuz your up high :) ahahhaah

[CAGftw00]

Hmm someone at some point has misguided you. Perhaps you or your parents grew up during reefer madness. Whatever. But here's the facts, not that you're interested.

THC (the active ingredient in Cannabis) causes your brain to produce an over abundance of Dopamine and Seratonin.

The effect that these influxes have on you is highly subjective and dependant on YOU. For some, the influx provokes spikes in creativity or memory. For some, it just causes laziness. Neither has to happen exclusively.

[beveah]

Admitted marijuana user too, huh that probably goes to show something I'll just leave it up to the anti-pot nazis to figure it out.

[sidewaysfcs0718]

him using pot doesnt change the fact that his documentaries present facts....

its not he was using pot DURING the filming...

[beveah]

I was saying that smoking pot obviously has no affect on intelligence or the capabilities of the mind...

[emceeDecree]

smoking pot can enhance the capabilities of the mind, though it often depends on the person's mental state and environment

[jegedy]

Carl is a one in a life time !! its just marvelous to watch him.

[Rokadonis]

@Manveet Sagan was a wizard fullstop.

[goog2k]

We are all walking, talking stardust,

this cosmos become AWAKE,

looking back at itself.

Thank you, Carl.

[Steadno]

time travel will start by us looking back and then recording it.

[mohfoz77]

CARL SAGAN we miss you dearly.

[elsope1]

circle559 your a fuckin dumb ass

[leporidus]

Ever used GPS in any way, circle559? There's relativity in your face.

[circle559]

stupid morons..we are not looking back in time because as the so called photons travel at light velocity time stops, thus no past, no future,, just present.. simple logic,, because time stops for the moving photon, it means that the photon at light velocity can reach any distance at no time at all, thus observed as instatanious by a observer. so time will not pass before light gets to your eye because at light speed time stands still.. yes, IF we go by relativity.. ha ha ha ha. any one?

[Pingletons]

You are the Moron. You're right, time becomes non-existant to the moving photon, but we are not photons flying around at the speed of light, are we. We, the actual people observing it, have a long while to wait, as we are not flying along that fast. Simple logic.

[Infynitra]

we can see the edge of the universe as it expands - and we can measure the edge of the universe as 13.7 +/- 0.1 billion light years away. Thus, the universe is 13.7 billion years old... or is it?

it has taken this light 13.7 billion years to reach us, thus it was emitted 13.7 billion years ago... so how large is the universe today?

[richiebabe24]

I thought the universe was finite but unbounded? That is to say, it doesn't have a size because all the matter in the universe causes it to curve back in on itself.

[CAGftw00]

That is the prevailing view of generations past, prior to the prevalence of the big bang. Astronomers today know that if the universe was created at a single point, then it must have definite edges, albeit expanding ones. So you are not completely off in this thinking...what you are saying was the widely accepted view prior to the prevalence of big bang thinking.

[KaiserTota]

We can see the edge of the universe? Where? When?

Who said such a thing?

[CAGftw00]

Yes we can. All around us. Any time you can use Hubble or Swift. Among others, Carl Sagan.

[circle559]

the universe is infinite in terms of magnitude.. dont be fooled..

[Infynitra]

indeed, the universe is infinite in magnitude, but the VISIBLE universe is finite.

[CAGftw00]

To answer your question, the edges of the observable universe are about 13.7 billion lightyears away. This figure comes from the fact that when we focus our telescopes as far as they can see, no information is returned beyond 13.7B LY away - its only static beyond that point. Also the light from that time was 'emitted' from the big bang - the start of all things. Ergo it hasnt taken 13.7B LY to reach us, but rather it has been there, at the edge of the universe, waiting to be seen, for 13.7B LY.

[andrewjohngordon]

"spent 75 years traversing intersetllar space" sounds like me trying to get the bus to work when I lived in the UK.

[defektev]

I don't know. I'm no skeptic, Carl Sagan has kind of given me new life from his grave. But I can't seem to conceptualize light we see from a star that has passed away long ago as a difference in time.

In a purely relative sense, yes. We are looking back into time, but only for that light. If I traveled out to that point, I wouldn't be further back in time but the information between us would rather be effected by time.

Love the channel btw. We need many more Carl Sagans.

[mikesoffel]

i gotta watch this high.

[lazzer408]

They were high when they filmed it so that only makes sense.

[sumfamousperson17]

"We cannot look out into space, without looking bad into time." Dang, I've honestly never though of it that way! :/

[underworld1]

Amazing videos, it's a shame that his warnings have gone unheeded and now political, economic and religious agendas are attempting to bar our intellectual progression.

[gydorack]

The speed of light actually has nothing to do with light.

A lot of people don't understand this.

If light could go faster than 300 thousand kilometers per second, it would.

The speed of light is a limit that can only be approached, but never reached. Not even information can travel faster than that.

[LampreyMoose]

Exactly. But I think that atoms can be "quantum entangled", and therefore affect eachother practically instantly, presumably faster than the speed of light.

[Gazzar]

The speed of light still applies to these scenarios as well. A flip in the quantum spin on one member of an entangled electron pair for example will not be registered on its entangled partner until some time equal to the distance between the two particles divided by the speed of light.

[Zotoaster]

The thing is about quantum entanglement is that there is no exchange of information, so it doesn't make sense to say "faster than the speed of light". They are supposed to occupy the same information, but just distanced by space.

[nightflyer28]

This was my fave program of 1980. Probably the only thing on PBS I watched regularly.

I wouldn't say that Sagan was the greatest scientist ever, but he certainly was the best at blending an intimate understanding of the various fields of science with a good, punchy writing style and had a great way of making such complex subjects comprehensible to pretty much anyone.

Thanks for posting these, Des. This is one series I think everyone should see at least once in their lives.

[JP5466]

Thanks for posting this. In 1980 I was 14 years old. Every Tueday night at 9pm I was tuned into my local PBS station watching amazing this show. It really made me think about the universe and how awesome it all is.

[XXXSDESDEXXX]

Your welcome. No matter how many times I watch these clips, I am struck with awe each time.

[toonuraccoon]

@XXXSDESDEXXX dude, I am like that right now. I watched these so amny times it's just so hard NOT to be impressed. Really truly awesome man is our Carl Sagan.