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Physicist Brian Greene takes you on a visual, conceptual, and mathematical exploration of Einstein’s spectacular insights into space, time, and energy. In just 11.5 hours, using nothing more advanced than high school algebra, journey from Einstein’s earliest musings on the speed of light to his startling realization that time can tick at different rates to his revolutionary discovery of the world’s most famous formula, E = mc2.
This is a more in-depth and mathematical version of the WSU Master Class “Space, Time, and Einstein.” https://youtu.be/CKJuC5CUMgU
#WorldSciU
Watch the class in full or view in segments via the chapter links below.
Experience the associated free online course at World Science U: https://worldscienceu.com/cour....ses/special-relativi
0:00 - Introduction
01:43 - Scale
05:46 - Speed
18:19 - The Speed of Light
27:39 - Units
33:28 - The Mathematics of Speed
44:24 - Relativity of Simultaneity
54:25 - Pitfalls: Relativity of Simultaneity
1:03:32 - Calculating the Time Difference
1:18:42 - Time in Motion
1:28:48 - How Fast Does Time Slow?
1:46:32 - The Mathematics of Slow Time
1:57:11 - Time Dilation Examples
2:10:51 - Time Dilation: Experimental Evidence
2:19:58 - The Reality of Past, Present, and Future
2:34:01 - Time Dilation: Intuitive Explanation
2:37:57 - Motion's Effect On Space
2:55:11 - Motion's Effect On Space: Mathematical Form
3:00:47 - Length Contraction: Travel of Proxima Centauri
3:07:46 - Length Contraction: Disintegrating Muons
3:12:00 - Length Contraction: Distant Spaceflight
3:18:54 - Length Contraction: Horizontal Light Clock In Motion
3:27:17 - Coordinates For Space
3:36:37 - Coordinates For Space: Rotation of Coordinate Frames
3:48:36 - Coordinates For Space: Translation of Coordinate Frames
3:53:10 - Coordinates for Time
4:07:12 - Coordinates in Motion
4:26:08 - Clocks in Motion: Examples
4:35:02 - Clocks in Motion: Length Expansion From Asynchronous Clocks
4:38:42 - Clocks in Motion: Bicycle Wheels
4:45:01 - Clocks in Motion: Temporal Order
4:54:35 - Clocks in Motion: How Observers Say the Other's Clock Runs Slow?
5:08:50 - The Lorentz Transformation
5:16:52 - The Lorentz Transformation: Relating Time Coordinates
5:26:10 - The Lorentz Transformation: Generalizations
5:33:18 - The Lorentz Transformation: The Big Picture Summary
5:47:37 - Lorentz Transformation: Moving Light Clock
5:54:39 - Lorentz Transformation: Future Baseball
6:02:35 - Lorentz Transformation: Speed of Light in a Moving Frame
6:08:43 - Lorentz Transformation: Sprinter
6:10:44 - Combining Velocities
6:17:46 - Combining Velocities: 3-Dimensions
6:27:45 - Combining Velocities: Example in 1D
6:30:23 - Combining Velocities: Example in 3D
6:36:34 - Spacetime Diagrams
6:50:35 - Spacetime Diagrams: Two Observers in Relative Motion
7:01:16 - Spacetime Diagrams: Essential Features
7:11:42 - Spacetime Diagrams: Demonstrations
7:15:23 - Lorentz Transformation: As An Exotic Rotation
7:27:26 - Reality of Past, Present, and Future: Mathematical Details
7:39:00 - Invariants
7:43:55 - Invariants: Spacetime Distance
7:54:25 - Invariants: Examples
7:59:19 - Cause and Effect: A Spacetime Invariant
8:12:40 - Cause and Effect: Same Place, Same Time
8:22:37 - Intuition and Time Dilation: Mathematical Approach
8:29:46 - The Pole in the Barn Paradox
8:43:51 - The Pole in the Barn: Quantitative Details
9:04:43 - The Pole in the Barn: Spacetime Diagrams
9:08:25 - Pole in the Barn: Lock the Doors
9:20:50 - The Twin Paradox
9:29:28 - The Twin Paradox: Without Acceleration
9:46:34 - The Twin Paradox: Spacetime Diagrams
9:53:12 - Twin Paradox: The Twins Communicate
10:06:34 - The Relativistic Doppler Effect
10:19:00 - Twin Paradox: The Twins Communicate Quantitative
10:30:17 - Implications of Mass
10:40:06 - Force and Energy
11:00:12 - Force and Energy: Relativistic Work and Kinetic Energy
11:07:24 - E=MC2
11:26:28 - Course Recap
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Probability is the examination of uncertain processes, but it's useful for far more than games of chance: http://www.gresham.ac.uk/lectu....res-and-events/proba
The modern theory of probability is considered to have begun in 1654 with an exchange of letters between Blaise Pascal and Pierre de Fermat, and has developed since then into the discipline which examines uncertain processes. For example, although on tossing a coin you have no idea whether you will obtain heads or tails we know that if you keep doing it then in the long run it is very likely that the proportion of heads will be close to a half. The lecture will discuss this and other examples of random processes e.g. random walks and Brownian motion.
The transcript and downloadable versions of the lecture are available from the Gresham College website: http://www.gresham.ac.uk/lectu....res-and-events/proba
Gresham College has been giving free public lectures since 1597. This tradition continues today with all of our five or so public lectures a week being made available for free download from our website. There are currently over 1,500 lectures free to access or download from the website.
Website: http://www.gresham.ac.uk
Twitter: http://twitter.com/GreshamCollege
Facebook: https://www.facebook.com/greshamcollege
Writing is generally agreed to be among the greatest inventions in human history, perhaps the greatest invention, since it made history possible.
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You can read more about Irving's quest to explore the Noah's Ark myth in "The Ark Before Noah: Decoding the Story of the Flood": https://geni.us/zU95bVO
or learn more about cuneiform writing in "Cuneiform": https://geni.us/eMPb
Writing seems to have been invented in the late fourth millennium BC in Mesopotamia in the form of wedge-shaped marks pressed into soft clay with a reed stylus: the script known as cuneiform. Through his work on this ancient language, Irving Finkel, has uncovered amazing secrets from over five thousand years ago, including the story behind Noah’s ark.
Irving Finkel is the curator in charge of cuneiform inscriptions on tablets of clay from ancient Mesopotamia at the British Museum, of which the Middle East Department has the largest collection of any modern museum. This work involves reading and translating all sorts of inscriptions, sometimes working on ancient archives to identify manuscripts that belong together, or even join to one another. He is the author of The Ark Before Noah: Decoding the Story of the Flood.
This talk was filmed in the Ri on 18 January 2019.
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Meet the brides and grooms defying the jihadist militants who have been laying siege to the Nigerian city of Maiduguri.
Subscribe to our channel for more Unreported World episodes https://www.youtube.com/unreportedworld.
Maiduguri is the spiritual home of Boko Haram, a terrorist group at the centre of an insurgency that has killed more than 36,000 people, and displaced over two million more.
With Covid lockdowns over, and the militants driven out, reporter Yousra Elbagir discovers a city determined to reclaim the joy of weddings despite the ongoing risk of kidnappings and attacks.
Producer/Director: Wil Davies
Executive Producer: Nevine Mabro
Series Producer: Andy Lee
Production Company: ITN/Channel 4 News