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2022-03-23: Where Is The Center of The Universe?

  • 03:04: General relativity can be used to calculate the spacetime curvature produced by the Earth or the Sun to determine their gravitational effects.

2022-02-23: Are Cosmic Strings Cracks in the Universe?

  • 10:09: ...   The other way to spot cosmic strings also  relies on a gravitational effect: gravitational   lensing - which is the warping of background ...

2022-01-27: How Does Gravity Escape A Black Hole?

  • 01:55: When you use those equations to calculate the speed of various gravitational effects, they also turn out to be the speed of light.
  • 08:54: To experience the gravitational effect of a massive object, the information about the presence of that mass does have to be able to reach you.
  • 09:12: ... below the event horizon, but we can see its past mass, and it’s the gravitational effect of the past mass that we actually ...

2022-01-19: How To Build The Universe in a Computer

  • 06:00: ... to clump particles  together and consider only  their summed gravitational effect. ...

2021-02-24: Does Time Cause Gravity?

  • 10:56: ... inflation it’s believed that quantum gravitational effects would have been very important, so if we can get any type of signal from ...

2020-05-18: Mapping the Multiverse

  • 12:23: That pressure produces its own gravitational effect on par with the black hole itself, accelerating the streams further.

2020-05-04: How We Know The Universe is Ancient

  • 11:07: ... - which is mostly in dark matter - can be found by adding up the gravitational effect in galaxies and in galaxy clusters, and also by tracking the past ...

2019-08-06: What Caused the Big Bang?

  • 02:43: Mostly, the stuff in the universe pulls the universe back together; resists the expansion with a positive gravitational effect.
  • 02:50: But there's one type of energy that can have an anti gravitational effect.

2019-04-24: No Dark Matter = Proof of Dark Matter?

  • 00:03: ... of Dunkel materia a dark matter invisible to the telescope but whose gravitational effect held the cluster together as with many of his wiki's predictions like ...

2019-04-03: The Edge of an Infinite Universe

  • 14:49: Every particle, every gravitational effect in the bulk is represented by quantum fields on an infinitely distant surface.

2019-02-20: Secrets of the Cosmic Microwave Background

  • 07:42: ... in the Universe Energy results in positive curvature due to its positive gravitational effect On the other hand an expanding universe with no energy would have ...

2019-01-24: The Crisis in Cosmology

  • 01:42: ...the rate of expansion of the universe, combined with the gravitational effect...

2019-01-09: Are Dark Matter And Dark Energy The Same?

  • 03:10: ... has competing effects – its positive energy density gives it a positive gravitational effect but its negative pressure is ...
  • 04:06: Forgetting that pressure stuff for a moment, positive masses and energies always have a positive gravitational effect.

2018-09-20: Quantum Gravity and the Hardest Problem in Physics

  • 04:38: ... that approach completely fails when you have strong gravitational effects on the smaller scales of space and time, like the central singularity of ...
  • 10:46: When you have strong gravitational effects on the quantum scale, the self-energy corrections blow up to infinity.

2018-09-05: The Black Hole Entropy Enigma

  • 00:53: Also, we've seen them in their gravitational effects on their surrounding space and in the gravitational waves caused when they merge.

2017-11-08: Zero-Point Energy Demystified

  • 05:32: The gravitational effect of energy depends on its absolute value.

2017-11-02: The Vacuum Catastrophe

  • 05:07: Vacuum energy should produce a gravitational effect, and a huge vacuum energy should produce a huge gravitational effect.

2017-10-25: The Missing Mass Mystery

  • 11:21: A non-zero vacuum energy would have a gravitational effect.

2017-02-15: Telescopes of Tomorrow

  • 09:06: ... the distant universe as their brightnesses fluctuate due to the changing gravitational effect of nearby massive ...

2016-12-14: Escape The Kugelblitz Challenge

  • 04:42: Now, light has energy and so has a gravitational effect.

2016-11-09: Did Dark Energy Just Disappear?

  • 00:52: They expected to see that this expansion rate was slowing down due to the gravitational effect of all of the matter in the universe.
  • 06:35: ... dark energy, and there are things that slow expansion, which is just the gravitational effect of regular energy, and that's mostly dark matter, but also stars, ...
  • 11:03: ... measure tells us that there has to be something out there countering the gravitational effect of matter and flattening the geometry of ...

2016-04-20: Why the Universe Needs Dark Energy

  • 00:52: ... of the universe and the resistance to this expansion due to the gravitational effect of everything it ...
  • 10:28: ... of the universe does include dark matter, which we can measure by its gravitational effect in several independent ...

2016-04-13: Will the Universe Expand Forever?

  • 05:40: But that oomph is resisted by the gravitational effect of all the master and energy in the universe.

2016-01-06: The True Nature of Matter and Mass

  • 01:22: Let's ignore the gravitational effect of mass for the moment, and just consider mass as the degree to which an object resists being accelerated.

2015-08-19: Do Events Inside Black Holes Happen?

  • 13:33: ... are gravitational effects from the Sun and Moon that do the same thing, but they're highly, highly ...

2015-07-02: Can a Circle Be a Straight Line?

  • 01:57: We'll end up seeing that all the supposedly gravitational effects on motion can be accounted for just by the geometry of spacetime.
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