The Fourth Dimension Explained, And the Real Evidence We Live In It.
Qosmix
171 views
Hold up your hand. Left-right, up-down, forward-back — three directions. Now try to point in a fourth, at right angles to all three. You can't. But mathematically that direction is perfectly defined, and physically there is very strong evidence it exists.
This is a full explainer: from 0D to 1D to 2D to 3D, how a tesseract is built and counted, what a four-dimensional object would look like passing through your room, why time is the fourth dimension of our universe, and how we know — measured with atomic clocks, cosmic ray muons, GPS satellites, a 1919 solar eclipse and a gravitational wave.
Every document and photograph in this video is a real archive source, public domain or Creative Commons, credited on screen and below.
CHAPTERS
0:00 The direction you cannot point at
0:49 0D to 3D: climbing the dimensions
1:37 Counting a shape you cannot picture
2:22 Flatland (1884): seeing in slices
3:15 Shadows of a higher dimension
3:54 Rotation in four dimensions
4:41 1905: Einstein and the speed of light
5:26 1908: Minkowski and spacetime
6:13 Why you move through time at light speed
7:00 The evidence: clocks, muons, GPS
7:48 1915: gravity is curvature
8:37 1919: the eclipse that proved it
9:25 2015: a ripple in spacetime
10:17 Kaluza, Klein and extra dimensions
11:06 How a dimension hides
11:56 The search: torsion balances and CERN
12:41 How you actually calculate 4D
13:23 You are already four-dimensional
KEY NUMBERS
· Tesseract: 16 corners, 32 edges, 24 square faces, 8 cubic cells
· GPS satellite clocks run ~38 microseconds per day fast (+45 from gravity, −7 from speed); uncorrected, navigation drifts ~10 km per day
· GW150914 (14 Sept 2015): black holes of ~36 and ~29 solar masses, peak strain ~1 part in 10^21 across 4 km arms
· String theory requires 10 or 11 dimensions; no extra spatial dimension has been observed
SOURCES AND FURTHER READING
· Edwin A. Abbott, Flatland: A Romance of Many Dimensions (1884)
· A. Einstein, "Zur Elektrodynamik bewegter Körper", Annalen der Physik vol. 17 (1905)
· H. Minkowski, "Raum und Zeit", lecture, Cologne, 1908
· F. W. Dyson, A. S. Eddington, C. Davidson, 1919 eclipse expedition results
· T. Kaluza (1921); O. Klein (1926) — five-dimensional unification
· LIGO/Virgo, "Observation of Gravitational Waves from a Binary Black Hole Merger", PRL 116, 061102 (2016)
· Hafele & Keating, atomic clock flights (1971); Eöt-Wash short-range gravity tests; ATLAS/CMS extra-dimension searches at CERN
IMAGE CREDITS (all public domain or Creative Commons, via Wikimedia Commons)
· Flatland (1884) cover and interior pages — Edwin Abbott Abbott — public domain
· Annalen der Physik, vol. 17 (1905) contents page — CC0
· The New York Times, 10 November 1919 and 25 November 1919 — public domain
· 1919 solar eclipse plate — Dyson / Eddington / Davidson — public domain
· Albert Einstein (1921, Underwood & Underwood), Hermann Minkowski, Theodor Kaluza, Oskar Klein — public domain
· GW150914 strain figure — Caltech/MIT/LIGO Laboratory — CC0
· Gravity Probe B — NASA — public domain
· Tesseract Schlegel diagram — Tomruen — CC BY-SA 3.0
· Calabi-Yau manifold cross-section — Lunch — CC BY-SA 2.5
· ATLAS detector, CERN — SimonWaldherr — CC BY-SA 4.0
Animation, motion graphics, music and sound design are original to this video.
TAGS
fourth dimension, 4th dimension explained, tesseract, hypercube, spacetime, Einstein relativity, Minkowski, time dilation, Flatland, extra dimensions, string theory, gravitational waves, physics documentary, how to visualise 4D
Hold up your hand. Left-right, up-down, forward-back — three directions. Now try to point in a fourth, at right angles to all three. You can't. But mathematically that direction is perfectly defined, and physically there is very strong evidence it exists.
Every document and photograph in this video is a real archive source, public domain or Creative Commons, credited on screen and below.
CHAPTERS
0:00 The direction you cannot point at
0:49 0D to 3D: climbing the dimensions
1:37 Counting a shape you cannot picture
2:22 Flatland (1884): seeing in slices
3:15 Shadows of a higher dimension
3:54 Rotation in four dimensions
4:41 1905: Einstein and the speed of light
5:26 1908: Minkowski and spacetime
6:13 Why you move through time at light speed
7:00 The evidence: clocks, muons, GPS
7:48 1915: gravity is curvature
8:37 1919: the eclipse that proved it
9:25 2015: a ripple in spacetime
10:17 Kaluza, Klein and extra dimensions
11:06 How a dimension hides
11:56 The search: torsion balances and CERN
12:41 How you actually calculate 4D
13:23 You are already four-dimensional
The Fourth Dimension Explained, And the Real Evidence We Live In It.
Qosmix
171 views
Hold up your hand. Left-right, up-down, forward-back — three directions. Now try to point in a fourth, at right angles to all three. You can't. But mathematically that direction is perfectly defined, and physically there is very strong evidence it exists.
This is a full explainer: from 0D to 1D to 2D to 3D, how a tesseract is built and counted, what a four-dimensional object would look like passing through your room, why time is the fourth dimension of our universe, and how we know — measured with atomic clocks, cosmic ray muons, GPS satellites, a 1919 solar eclipse and a gravitational wave.
Every document and photograph in this video is a real archive source, public domain or Creative Commons, credited on screen and below.
CHAPTERS
0:00 The direction you cannot point at
0:49 0D to 3D: climbing the dimensions
1:37 Counting a shape you cannot picture
2:22 Flatland (1884): seeing in slices
3:15 Shadows of a higher dimension
3:54 Rotation in four dimensions
4:41 1905: Einstein and the speed of light
5:26 1908: Minkowski and spacetime
6:13 Why you move through time at light speed
7:00 The evidence: clocks, muons, GPS
7:48 1915: gravity is curvature
8:37 1919: the eclipse that proved it
9:25 2015: a ripple in spacetime
10:17 Kaluza, Klein and extra dimensions
11:06 How a dimension hides
11:56 The search: torsion balances and CERN
12:41 How you actually calculate 4D
13:23 You are already four-dimensional
KEY NUMBERS
· Tesseract: 16 corners, 32 edges, 24 square faces, 8 cubic cells
· GPS satellite clocks run ~38 microseconds per day fast (+45 from gravity, −7 from speed); uncorrected, navigation drifts ~10 km per day
· GW150914 (14 Sept 2015): black holes of ~36 and ~29 solar masses, peak strain ~1 part in 10^21 across 4 km arms
· String theory requires 10 or 11 dimensions; no extra spatial dimension has been observed
SOURCES AND FURTHER READING
· Edwin A. Abbott, Flatland: A Romance of Many Dimensions (1884)
· A. Einstein, "Zur Elektrodynamik bewegter Körper", Annalen der Physik vol. 17 (1905)
· H. Minkowski, "Raum und Zeit", lecture, Cologne, 1908
· F. W. Dyson, A. S. Eddington, C. Davidson, 1919 eclipse expedition results
· T. Kaluza (1921); O. Klein (1926) — five-dimensional unification
· LIGO/Virgo, "Observation of Gravitational Waves from a Binary Black Hole Merger", PRL 116, 061102 (2016)
· Hafele & Keating, atomic clock flights (1971); Eöt-Wash short-range gravity tests; ATLAS/CMS extra-dimension searches at CERN
IMAGE CREDITS (all public domain or Creative Commons, via Wikimedia Commons)
· Flatland (1884) cover and interior pages — Edwin Abbott Abbott — public domain
· Annalen der Physik, vol. 17 (1905) contents page — CC0
· The New York Times, 10 November 1919 and 25 November 1919 — public domain
· 1919 solar eclipse plate — Dyson / Eddington / Davidson — public domain
· Albert Einstein (1921, Underwood & Underwood), Hermann Minkowski, Theodor Kaluza, Oskar Klein — public domain
· GW150914 strain figure — Caltech/MIT/LIGO Laboratory — CC0
· Gravity Probe B — NASA — public domain
· Tesseract Schlegel diagram — Tomruen — CC BY-SA 3.0
· Calabi-Yau manifold cross-section — Lunch — CC BY-SA 2.5
· ATLAS detector, CERN — SimonWaldherr — CC BY-SA 4.0
Animation, motion graphics, music and sound design are original to this video.
TAGS
fourth dimension, 4th dimension explained, tesseract, hypercube, spacetime, Einstein relativity, Minkowski, time dilation, Flatland, extra dimensions, string theory, gravitational waves, physics documentary, how to visualise 4D
Hold up your hand. Left-right, up-down, forward-back — three directions. Now try to point in a fourth, at right angles to all three. You can't. But mathematically that direction is perfectly defined, and physically there is very strong evidence it exists.
Every document and photograph in this video is a real archive source, public domain or Creative Commons, credited on screen and below.
CHAPTERS
0:00 The direction you cannot point at
0:49 0D to 3D: climbing the dimensions
1:37 Counting a shape you cannot picture
2:22 Flatland (1884): seeing in slices
3:15 Shadows of a higher dimension
3:54 Rotation in four dimensions
4:41 1905: Einstein and the speed of light
5:26 1908: Minkowski and spacetime
6:13 Why you move through time at light speed
7:00 The evidence: clocks, muons, GPS
7:48 1915: gravity is curvature
8:37 1919: the eclipse that proved it
9:25 2015: a ripple in spacetime
10:17 Kaluza, Klein and extra dimensions
11:06 How a dimension hides
11:56 The search: torsion balances and CERN
12:41 How you actually calculate 4D
13:23 You are already four-dimensional