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Neil Tyson On Humanity's Chances Of Interaction With Aliens

kronosposeidon says...

^You say:

I believe that the difference between the average human being and Stephen Hawking is far larger then the difference between the average human and the chimpanzee.

But that's not true. Like he said, the average human child (and even most stupid ones) can do tasks that are just too complicated even for the smartest chimps. Also, Stephen Hawking is a genius when it comes to astrophysics, but he's not a genius at everything. I'm sure he'd agree with that. Bach was a musical genius, Shakespeare was a literary genius, Kurosawa was a film making genius, etc. But all these geniuses were pretty normal in most other aspects of their intellect. Dr. Tyson is saying, I believe, that aliens who are just 1% more genetically "advanced" (for lack of a better word), would be intellectually superior to us in just about everything. Their grasp of science would be superior, and so would their communications skills, their conceptual skills, and maybe even their art skills. Maybe they could all paint like Michaelangelo, compose like Beethoven, write like Jane Austen, and so on.

It might seem far-fetched, but just because it's hard to imagine doesn't mean it isn't possible. And "intelligent" life might be far more abundant than even the most optimistic scientists predict. So who knows? We know so very little, that it's almost laughable, really.

Neil deGrasse Tyson Opening a Model Rocket

honkeytonk73 says...

He is one of the coolest guys ever. I'd love to meet and have a chat with him in person. Almost wish I continued in my study of astrophysics instead of switching to the computer engineering field. Just for the slight chance to be able to work with him.

Physics - Fusion and Fission

dannym3141 says...

>> ^RhesusMonk:
Question regarding fusion: If the binding energies of the two hydrogen isotopes equal 10 MeV, and the binding energy of helium is 28 MeV, wouldn't the fusion require the input of 18 MeV? I don't understand. Doesn't the helium require more energy to hold together than the hydrogen isotopes had to begin with? And, even if the nucleons do just come together, how is there surplus energy if less energy went into the reaction than exists in the product?


Ok, it's a long time since i even looked at physics, but i'm gonna study astrophysics next year so i better make at least an attempt

The electromagnetic force repels the nucleons from each other. The nuclear force attracts them to each other. You have to force the two together. That requires you to overcome the electromagnetic force. So you only need enough energy to do this, and the energy required to do this is usually LESS than the energy that is released for atoms 'below' iron.

The energy basically comes from a conversion of mass to energy. The mass of the combined atoms is not quite equal to the mass of the parts that you combine. Mass is lost, and it manifests as energy. (because e=mc^2, or in other words, energy and mass are 'interchangeable' - you cannot just 'lose' mass)

Black Holes

botelho says...

Well, space-time coordinate of one of those space-time manifold charts (covering the space-time manifold) is one object that you certainly can "travel" back and forth(remember Godel formal PDE's solution for Einstein equation ). However , what realy counts and play the role of the Newtonian time in general Einstein relativity is the unique proper-time of a given event !(this can not be back!). Note that still remains a problem to "adjust" colectivelly the proper time of several geodesics associated to the motion of several particles moving in the back ground of a given relativistic gravitational field (The twin paradox has not been fully understood !).Let me explain better : In the Einstein framework , one gives a certain energy-momentum configuration (the "Sun") (mathematically a tensor of rank two in relation to the Local dipheomorffism space-time manifold group) in the (tensorial bundle) of space-time manifold :a object from the beginning possesing solely a differentiable topological structure and after that (and if compatible with the manifold topology-Chern /Gauss theorem constraint, Riemann completeness ,etc..), one determines the topologically compatible local metric structure of the smooth space-time by means of the famous Einstein Equations.If everything is smooth from a geometrical point of view , one starts the prediction of the "falling" bodies trajectories in this gravitational field throught the solution of the Boundary-Value Sturm liouville like problem associated to the geodesics non linear equations (you should know the beginning and the final point of the falling body trajectory into the space-time ,not the initial point and its "initial velocity" as in Newton Equation).Now one can make further steps on the Einstein program by exchanging the mater-energy Einstein's source by boundary ad-hoc conditions simulating point sources -delta sources-(not dipheomorffism covariant) ,like the Schwartz-Schild solution for Einsteinian particle motions around the Sun), and thus leading to a rich mathematical universe ( astronomical and astrophysical/cosmological observable ?)

This Happens When You Ask God if Wormholes Exist

Nightline Face-Off - Does Satan Exist?

ponceleon says...

I said it in the other post about hookers for jesus...

The idea that someone who thought that being a prostitute was a good idea is now going to try to convince me that a magical guy in the sky controls (or doesn't) everything, is kind of stupid.

If the hooker had decided to tell me about feminism, I'd be more impressed. It shows actual growth and insight. Hookers for Feminism, sure. Hookers for Astrophysics, sure. Hookers for Jesus? Whatever.

David Attenborough on God

Lodurr says...

>> ^Skeeve:
From the attacks of 9/11 (which have been used as a justification for Iraq) to the sectarian violence ravaging Iraq right now, god/religion is the main killer there too.


I just wanted to point out that it's really misguided to say that religion caused all these conflicts which happened to have religion tacked on to them. The Crusades, for example, were less about religion than they were about halting the advance of a growing empire. Religion is the excuse and the propaganda tool for mobilizing one group of people against another, usually for political reasons or in competition over resources. We'd have plenty of wars still without religion, and the scapegoating is pointless.

>> ^rottenseed:
And as for eastern religions Hinduism, Buddhism, etc; all that spiritual stuff, is BS in my book.

You clearly haven't researched them at all. Some aspects of Hinduism and Buddhism aren't spiritual but pragmatic. Then there's Taoist philosophy which is agnostic when it comes to belief in a soul or an afterlife, but it teaches that ultimately it doesn't matter. I see modern astrophysics and quantum physics making new hypotheses that mirror Eastern philosophical tenets, such as cosmic inflation theory's infinite/eternal field of bubble universes being similar to the Tao. Eastern philosophies can't be lumped in with Western religions, and aren't adequately described as "spiritual stuff."

Hookers for Jesus

ponceleon says...

So, let me get this straight... a woman who thought that the sex trade business was a good idea is now going to tell me about the magical guy who lives in the sky?

I think "Hookers for Astrophysics" would have been more of a shock for me...

honkeytonk73 (Member Profile)

budzos says...

Sounds like you're involved in some pretty interesting circles!

In reply to this comment by honkeytonk73:
Yes, a really nice guy. His talk was quite 'out there' by most standards, but a man of his stature most definitely has the right to go out on a limb with ideas that challenge the establishment and help foster alternative ways of thinking. If you check the twitter for 'exoplanetology.org', they have a pretty good running commentary on what was discussed Friday/Saturday during the crossroads conference at Harvard.

I also met Prof David Charbonneau, one of the leading astronomers in the search for exoplanets. Really nice guy as well. I got some pointers on how I could contribute to the search. Being an amateur astronomer/astrophotographer, I wanted to try to get more involved and help provide observations/data. Of course I suspect I have a bit of a learning curve to climb, but that is half the fun.

They have a month of science in Cambridge/Harvard every year. With events, talks and the like. I suspect they'll try to put together another such event next year. Search for the harvard smithsonian center for astrophysics. A person by the name of Christine Pulliam has a mailing list for sponsored events.. from talks by scientists, to SciFi B-Movie night. Quite funny. Sometimes these talks are webcast, so for certain events you don't have to be local!

Mauru (Member Profile)

dannym3141 says...

I can only repeat what i said on the thread, it's the most hate mongering fear factor old shite that i've ever heard.. i dunno where they dragged him up from but i'm sure it wasn't a university nor a list of qualified solar experts. Whispering "this is a worst case scenario BUT SHIT COULD GET REAL LOOK OUT EVERYONE BUILD A BUNKER BE SCARED OF THE SUN HE'S GOING TO THROW HIS ANCIENT TEMPER TANTRUM LAST TIME THIS HAPPENED WE LOST THE TOWER OF BABEL!"

Sorry but it's absolute bollocks and i enjoyed ripping into him. If they presented me with a physics expert who used scientific terms instead of emotional terms, i'd listen and say "hmmm, interesting!" cos i actually love science especially astrophysics. But presenting me with 'some bloke' that tells me to be scared and that the sun is 'throwing a wobbler' - which i assume is a technical scientific term so i don't understand it completely, he's talking way too far above my head - is just stupid.

In reply to this comment by Mauru:
In reply to this comment by dannym3141:
...

Don't get so worked up Danny- he repeatedly mentioned it is a WORST CASE scenario, i.e. very, very unlikely to happen- I agree he could have mentioned the odds or sth, but the fact that the sun has cycles and that things like this happened before seems rather interesting to me (and not really all that scary).

budzos (Member Profile)

honkeytonk73 says...

Yes, a really nice guy. His talk was quite 'out there' by most standards, but a man of his stature most definitely has the right to go out on a limb with ideas that challenge the establishment and help foster alternative ways of thinking. If you check the twitter for 'exoplanetology.org', they have a pretty good running commentary on what was discussed Friday/Saturday during the crossroads conference at Harvard.

I also met Prof David Charbonneau, one of the leading astronomers in the search for exoplanets. Really nice guy as well. I got some pointers on how I could contribute to the search. Being an amateur astronomer/astrophotographer, I wanted to try to get more involved and help provide observations/data. Of course I suspect I have a bit of a learning curve to climb, but that is half the fun.

They have a month of science in Cambridge/Harvard every year. With events, talks and the like. I suspect they'll try to put together another such event next year. Search for the harvard smithsonian center for astrophysics. A person by the name of Christine Pulliam has a mailing list for sponsored events.. from talks by scientists, to SciFi B-Movie night. Quite funny. Sometimes these talks are webcast, so for certain events you don't have to be local!


In reply to this comment by budzos:
Really? You met Freeman Dyson? That's fucking awesome! He's one of my heroes!

In reply to this comment by honkeytonk73:
VERY nice clip. Surprised to see Professor Freeman Dyson there. I just met the man just a days ago. We were both heading to the same place, and accompanied him to a talk near Harvard College. He was among a few other amazing speakers. They discussed the future of mankind, the search for exoplanets, detecting live elsewhere and the like.

Dr Quantum Visits a 2-Dimensional World

dannym3141 says...

Oh dude... you're so completely missing the point, ornthoron. It's so completely basic that you've overstepped it in your intelligence.

They're not trying to trick you! They're trying to challenge people to think more, to learn more and to try harder and reach for the stars. Inflame a childlike fiery burn for knowledge and understanding, and trying to hint that while we may think we know so much, there could be so much more that we don't know, and that may or may not be better and more fulfilling than what we know now.

They are giving it new meaning and trying to promise that we can be so much more, because that's the driving force that makes people try to reach further than they know they can.. and while they might even grasp something short of what they wanted, it was further than we were to begin with.

God man, this is the sort of thing that inspired me when i was younger, it skews your viewpoint and then, in majestic and mysterious ways, it says..... LOOK what we could discover, look what thinking and learning and discovering can do for us. This and shows like it is what drove my interest (and still drives it, in a way). My dad probably looked at videos i used to watch like this and saw that it was common knowledge, it wasn't necessarily as gargantuan an idea to him as it was to me, and it wasn't always necessarily exact in the strictest sense, but he knew to encourage me and when i looked at him and asked him (an astrophysics teacher) "is that true? is it really that amazing?" he'd say "yep, and even more than that... look at this.." and tell me something else that may not have been exact, but drove me onwards and inflamed my desire to know more, to know everything.

And he knew that one day i'd come back to him and say, "You were wrong! It doesn't work the way you told me, I LOOKED IT UP AND FOUND OUT FOR MYSELF!" And what better prize is there than that? And i'd go on to discuss other related things with him, which may or may not have been 100% exact as well

It's so sad to me that you didn't see that in this video. I think it shows the effect that cynicism and time can have on a person.

The Wonders of Electricity and Magnetism

mauz15 says...

About the Speaker
Walter Lewin

Professor of Physics

Walter H. G. Lewin is well-known at MIT for his lectures on both Newtonian mechanics and electricity and magnetism. Videos of his lectures can be viewed on the web via the Open CourseWare and Pivot links below.

Lewin received his Ph.D. in Nuclear Physics in 1965 at the Technical University of Delft, The Netherlands, and has been a member of the MIT Physics faculty since 1966. During his MIT career, Lewin's investigations in astrophysics have included satellite and high-altitude balloon X-ray observations, world-wide coordinated observations of optical and X-ray bursts, and international collaborations observing X-ray sources. In addition, Lewin has collaborated over the years with various artists on sky art events. From 1998 to 2000, Lewin worked with MIT's Center for Advanced Educational Services on creating the Physics Interactive Video Tutor project -- video help sessions for freshman physics students.

$1000 Dollars To Any Atheist Who Can Prove A Negative

dannym3141 says...

>> ^spoco2:
Also, I quite like this video response: http://au.youtube.com/watch?v=8G3osI7Nrw4
Although in it he says that he doesn't believe that the sun will come every day, in fact he's always skeptical it will. Which is fine and all in regards to getting the point across, but also is a little silly. Once you get to a certain point of having gathered enough data, and seen something fit a model perfectly for a long time, I think it's pretty reasonable to assume and be comfortable with assuming that said sun is going to rise at the prescribed time the next day.


It's 50/50. My dad is a physicist and has high qualifications in astrophysics which i won't go into detail about, but as i was growing up and gaining a healthy interest in physics he told me once that, as a scientist, he had to accept that he may wake up tomorrow and gravity had taken a holiday. I think all scientists get the point there. He was trying to get across to my adolescent mind a point about science.

It's not saying that it's likely or even that it will somehow come as justification for his skepticism. It's trying to say that science is about testing, testing, testing, retesting, and observing the results. When you see enough of the same result, you make a hypothesis, you stick to that hypothesis for as long as you continue to see the same result. You should always go into the experiment (in this case waking up, seeing if you're subject to gravity) without expectations, in case you screw your observations up.

So you're right that you can be safe and comfortable and reasonable to assume the things we know to be true will continue to be true, but you should always be skeptical for science.

And to the above poster, who is to say that the nature of mass and energy won't change to allow smaller mass stars to go supernova? We can't know! This is the point!

stephen hawking's universe 05 : black holes, aliens

siftbot says...

Tags for this video have been changed from 'stephen hawking, cosmology, black holes' to 'stephen hawking, cosmology, astrophysics, physics, black holes, universe' - edited by mauz15



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