Hr Videos

Alex Filippenko: “Dark Energy and the Runaway Universe” | Talks at Google

We expected the attractive force of gravity to slow down the rate at which the Universe is expanding. But observations of very distant exploding stars (supernovae) show that the expansion rate is actually speeding up, a remarkable discovery that was honored with the 2011 Nobel Prize in Physics to the teams’ leaders. Over the largest distances, the Universe seems to be dominated by a repulsive “dark energy” — an idea Albert Einstein had suggested in 1917 but renounced in 1929 as his “biggest blunder.” It stretches space itself faster and faster with time. But the physical origin and nature of dark energy, which makes up about 70% of the contents of the Universe, is probably the most important unsolved problem in all of physics; it may provide clues to a unified quantum theory of gravity.

About the Speaker: Alex Filippenko is the Richard & Rhoda Goldman Distinguished Professor in the Physical Sciences. His accomplishments, documented in about 700 research papers, have been recognized by several major prizes, and he is one of the world’s most highly cited astronomers. In 2009 he was elected to the National Academy of Sciences, and he shared part of the Gruber Cosmology Prize in 2007. He has won the top teaching awards at UC Berkeley and has been voted the “Best Professor” on campus a record 9 times. In 2006 he was selected as the Carnegie/CASE National Professor of the Year among doctoral institutions, and in 2010 he won the ASP’s Emmons Award for undergraduate teaching. He has produced five astronomy video courses with “The Great Courses,” coauthored an award-winning textbook, and appears in numerous TV documentaries including about 40 episodes of “The Universe” series. An avid tennis player, hiker, and skier, he enjoys world travel and is addicted to observing total solar eclipses (11 so far).


Show More

Related Articles


  1. Everything Alex has discussed here in this video is based upon the supposition that there was a 'big bang'. Very complex and elaborate. It's a finite theory that helps to rule out the possibility of a multiverse and it's influences. Of course, none of these proposals and theories would be true if that were the case. I really enjoyed this lecture however. Thanks Alex.

  2. Such BS wanna ruffle mainstream cosmology's panties just mention Immanuel Velikovsky lol find out why they swept the findings of Halton Arp under the rug, & took his telescope time away. It is rather dastardly but he will have the last laugh. Cosmology quest search it I dare ya. These bozos got a lotta nerve. Lol, it's called the king's new clothes. Their unprovable ad-hok theories thanks to the internet are headed for the heap bin of history. Horse n buggy cosmology, Tesla was right. Check out Wal Thornhill and the Thunderbolts group where real science is being done and it's getting bigger and bigger every day. The cat is out of the bag folks learn about plasma physics and the electric universe. Don't defend your prison. The 21st century has arrived.

  3. I am concerned, that the description, of dark matter/energy is very similar to the properties of light (photons). they power gravity, matter and are energy, and have electro-magnetic properties.(proven by gravitational lensing of light) gravity has a limited distance after which solar wind (photonic pressure) would push matter including galaxies at an ever increasing rate. there are four locations that effect this push 1. in proximity to gravity 2. in the center of the universe where light from all directions push in all directions, 3. near the edge of the universe where the push is in all but one direction, and 4. outside the universe where all light is pushing out of the universe. thus the acceleration. (like the time it takes for a photon to escape from the center of the sun.) we can only see photons when they are coming to us but away we can not see. like escape velocity gravity's power has limits. but the universe has been being filled by photons since the big bang and the light from all the suns from all the galaxies. pushing against each other explains the expansion easily. energy is neither created nor destroyed. it joins with matter and is released from matter thus all photons from the beginning are still there traveling in space or locked in matter. space is static it is not expanding only the matter in it that is moving. a body in motion will stay in motion until reacted on by an outside force. (photonic pressure for thirteen billion years?) this will continue until all light is expended (escapes the universe's matter unless it finds something out there, but not likely or we would have evidence of the matter at the edge of the universe contacting something that slowed it down changing it's red shift,) then there will no longer be any acceleration. matter will continue at that rate. and lastly when matter is heated it changes from state to state ("atomic compressed" like a black hole, a solid, a liquid, a gas, and as plasma.)  expanding until it cools

  4. Алекс Филиппенко – это просто смех, а не учёный! Как этого клоуна можно воспринимать!

  5. Time is created by the speed difference between slow resting mass energy (that includes you and me) and fast light speed energy.

    As you you move faster toward the speed of light your time continues to slow until you reach light speed, at which your time stops and does not move forward or back. The speed of light aka universal constant is one anchor point in time with you being the other.

    This is why everyone experiences time on a unique personal basis. You are the other anchor point. All matter is one anchor point in time and is why all matter ages.

    The gap that is created between slow resting mass energy and faster light speed energy (xrays, light, gamma rays, radio waves, etc) is what we call 3D space.

    At the speed of light both time and distance are zero. The earth has a diameter of zero! Both space and time rely on this matter to constant relationship.

    One mechanism makes both, which is why time and space are dynamically connected.
    It’s cool how one matter to light speed (universal constant) mechanism can make something that is 1D and something 3D.

    Gravity appears to be the interference of the full matter to constant relationship. Basically matter gets partially in the way of other matter thus causing a decrease in the expansion of space directly between the matter causing them to move directly together.

    For the full story (easy to read)


  6. he may have suggested Dark Matter, ahead of his time, but noone knows what it is, if it is matter.  So, he was only ahead of his time in thinking what current scientist think.  But you might all be wrong.

  7. I believe dark energy is a positive pressure exerted by the vacuum energy of space-time, and that what we are calling dark matter is merely the effects of dark energy on regular matter.

    A positive pressure exerted by space-time's vacuum energy predicts;
    -the accelerating universe
    -the expanding universe
    -we should measure there to be more mass than we can see matter being accountable for
    -matter in the center of a galaxy / cluster should have added relativistic mass, increasing its gravitational attraction, as well as its escape velocity
    -matter in the outer regions of a galaxy / cluster should be moving faster than we predict, sometimes faster than our predicted maximum orbital speed without flying out of orbit.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Back to top button
%d bloggers like this: