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Paradoxes od vaccum from ancient metaphysics to present day physics Peter Zamarovský ČVUT, FEL,...
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Transcript of Paradoxes od vaccum from ancient metaphysics to present day physics Peter Zamarovský ČVUT, FEL,...
Paradoxes od vaccum from ancient metaphysics to present day physics
Peter Zamarovský ČVUT, FEL, Technická 2, Praha 6
“I love talking about nothing. It is the only thing I know
anything about.” G.B. Shaw
Definition of the concept of vacuum
Socrates – exact definition of concepts
Neologisms → hypostasis give rise of FORMS (Plato)
Delineation (A. W. Watts)
Leitmotif of analytical philosophy – improvement of language → epistemology → ontology → knowledge (science)
Problems with the concept of vacuum
Concept of vacuum (KENON) – not clear (AITHER, AER …) Empedocles: aer is of material nature (KLEPSHYDRA)AER filling of Cosmos ?Archytas of Tarentum – music of spheres(?), Kepler (17th cent.) – Somnium (Moonflight dream) – aer on MoonVacuum – absence of palpable (solid ?) matter
Logical proof of nonexistence of vacuumParmenides – PERI FYSEÓS (On Nature)(difficult metaphysical poem ) - paradox of negative existentials
No-beingness is neither perceptible nor knowable But: “to be conceived” and “to be” is the same(there is only one criterion of being – our thinking, conceiving
(NOEIN))From this: No-beingness (ME ON) does not exist!
Cyclops Polyphemos Odysseus: I am Nobody: No provident to use negative concepts!
Problems with the concept of vacuum
Melissos of Samos – jump to physical level
“Nor is anything empty, because to be empty means to be nothing and to be nothing means not to be.”
“Vacuum” (KENON) – contradictory concept (pseudoconcept) – does not correspond to anything
Later (Aristotle):
+ physical argument HORROR VACUI
Problems with the concept of vacuum
Descartes (1596-1650): corpuscular space„If a vessel would be completely empty, its walls
would be in mutual contact, as nothing would be among them.“
Thomas Hobbes (1588-1669): Boyle (Robert Boyle 1627-91) supposition that gas consists of particles moving in free space (kinetic theory of gases) can not be correct – there is no free space!
Newton (1642-1727)Absolute (free) space - SENSORIUM DEI(accelerated, rotational motion with respect to the
“absolute space”)
Another way: vacuum exists
Leucippus
Universe consists from fullness and emptiness. The Emptiness is no less then the fullness.
Aristotle
... Those who try to show that there is no free space … do not understand it … they suppose that everything that exist must be bodily.
Physics IV, 214a, 17-30
Vacuum
However:Inertia testify against existence of emptiness.
Aristotle, Physics VIII.
Epicureans and Stoics:
It is therefore the space is empty and nonpalpable. Otherwise, in no way things could move.
Lucretius Carus (cca 50 BC), De Rerum Natura
Period of classical physics
J. E. Torriceli, Perrier, Otto von Guericke, “technical vacuum”
Period of modern (classical) physics
End of SENSORIUM DEI Inertial system (Lang- circular definition)
E. Mach: Mach principle (Einstein): “Inertial forces” have to be caused by mass of
the Universe, no by “empty space” (Close masses evidently do not play any role.)
A. Einstein – OTR Tensor of gravitational field
Optics
Light wave nature (Young experiments, interference)
What is undulating?
Ether.
Ether is
1. Fulfill the space
2. Creates the space
Ether fulfill the space
Simon Newcomb (1878)John Gore (1888)Bubbles (drops) ofether (dark sky paradox)
But: Polarization of light → Transversal waves!Problems with modeling etherExperiments of Michelson and Morley (1881, 1887) →
constant speed of light, end of ether
Current statusSubstantial understanding, vacuum is not emptiness
but fullness, even fundamental fullness
• “school physics”, Newtonian approximation, mechanics: vacuum = empty space (how much “empty?”)
• Deeper approximation of present physics: OTR – tensor field QED – sea of virtual particles
Some new aspects: Return of the absolute space (?)Commoving systemRelict radiation (Cosmic background
radiation)
Hidden energy of vacuum – QEDDiscovery of accelerated expansion of
universe (1998) „dark energy“
There is no unifying view.