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Teleparallel Treatment of theEhrenfest, Sagnac and Field
Rotation Paradoxes
William M. Pezzaglia
Department of PhysicsSanta Clara UniversitySanta Clara, CA 95053
Email: [email protected]
• Rotating Frames are Equivalent to Torsion
• Torsion Explains Sagnac & Ehrenfest
• Possible solution to Schiff field rotation paradox?
21st Pacific Coast Gravity Meeting, Univ Oregon 2005Mar25-26
http://www.clifford.org/∼wpezzag/talks.html
INDEX
Talk 4:45 pm, Friday 2005Mar25
Title 1
Index 2
I. Rotational Relativity 3
II. Harres-Sagnac Effect 4
III. Ehrenfest Paradox 5
IV. Field Rotation Paradox 6
V. Simultaneity and Spacetime Split 7
VI. Anholonomic Transformation 8
VII. Teleparallel Coordinates 9
VIII. Principles and Paradoxes 10
IX. Barnett/Feynman Paradox 11
X. Schiff Paradox 12
XI. Partial Solution 13
XII. Charge and Invariance 14
XIII. Special EM Rotational Relativity 15
XIV. Some Points 16
XV. References 17
III. Ehrenfest Paradox
A). Born’s Off-Diagonal Metric (1909)
Galilean Coordinate
Transformation
t′ = t
θ′ = θ − ωt
ds2 = [c2 − ω2r2]dt′2︸ ︷︷ ︸Centrifugal
− 2ωr2dθ′dt′︸ ︷︷ ︸Coriolis
− r2dθ′2 − dr2
• Cross term describes Coriolis and Sagnac
• Circumference (dt′ = 0): C′ = 2πris Born rigid (unchanged)
B). Ehrenfest Paradox (1909)
•Lab Frame: Circumference must be Lorentzcontracted while radius is not: C < 2πr
•Rot Frame: Einstein argues setting disc intorotation dynamically stretches circumferenceby curving space (i.e. not Born rigid):
C′ = γ2πr
C = C′/γ = 2πr
γ ≡ 1√1−ω2r2
c2
•But Born metric is FLAT. Contradiction!
V. Simultaneity: Spacetime Split
A). Orthogonalize Time
• Observers require: time ⊥ space
• Born metric has: g4θ 6= 0
• Langevin(1935), Adler, Bazin, Schiffer(1975) redefine time: dt?2 = dt′ − γ2ωr2
c2dθ′
Metric: ds2 = (c2 − ω2r2)dt?2 − γ2r2dθ?2 − dr2
B). Ehrenfest Paradox Explained
• Length measurement require: dt? = 0
• Rotating Frame Circumference: C′ = γ2πr
• Lab Frame: C′ = C′/γ = 2πr
C). Fix one thing, break something else
• Sagnac Effect now unexplainable
• Coriolis Missing?{
θr4
}=
{rθ4
}= 0
• Curvature induced (but how?)
• Rotation Addition Formula Bad
VI. Anholonomic Transformation
A). How did we induce curvature?
• Adler’s coordinate transformation is nonholonomic(dt?
dθ?
)=
[γ2 −γ2r2ω/c2
−ω 1
] (dtdθ
)
• dt? non-integrable (path-dependent)
• Curvature and Torsion induced (Kleinert 1997)
B). Sagnac Effect from Torsion
• τ4rθ = Γ4
rθ − Γ4θr =
[∂
∂r?,∂
∂θ?
]t = 2γ4rω
c2
• Sagnac as non-closure (Corum 1977)
∆T =∮
dt =∫
drdθ τ4rθ = 2ωπR2
c2−ω2R2
C). Adler’s is Riemann-Cartan
• Connection: Γσµν =
{σµν
}+ Kσ
µν
• Metrical Connection gives Centrifugal:{
r44
}
• Contorsion gives Coriolis: Kθr4 , Kr
θ4
VII. Teleparallel Coordinates
A). Want Relativistic Theory
• Observers require Local Lorentz Frame with fixed “c”
• Born metric has non-orthogonal time: g4θ 6= 0
• Adler/Langevin has non-orthogonal space: g12 6= 0
B). Anholonomic Frame
• Franklin(1922), Trocheres(1949), Takeno(1952), Co-
rum(1977, 1980) suggest angular Lorentz Transf.,
dt′ = γ(dt− ωr2/c2 dθ)
dθ′ = γ(dθ − ωdt)
• Flat Metric: ds2 = c2dt′2 − r2dθ′2 − dr2
C). All Phenomena from Torsion
• Sagnac from: τ4rθ = 2γ2rω/c2
• Ehrenfest/Thomas Precession from τθrθ = γ2rω2/c2
• Clock Asynchronization from: τ4r4 = γ2rω2/c2
• Contorsions give kinematics,
Kθr4 , Kr
θ4 (Coriolis)
Krθθ (Centripetal), Kr
44 (Centrifugal)
VIII. Principles and Paradoxes
A). Special Rotational Relativity
• Carmeli(1986): “The laws of physics are the same in
all rotationally unaccelerated systems (bodies) having
constant angular velocities relative to each other”
• Paradoxes show there is no special theory of
rotational relativity. Carmeli’s idea didn’t work.
B). General Rotational Relativity
• Einstein: Accelerated reference frame is equivalent to
a frame at rest with curvature
• Propose: Rotating reference frame is equivalent
to a frame at rest with torsion
C). Rotational Electrodynamics
• Corum(1980) has shown that rotationallyconsistant electrodynamics requires torsion
Gauge Dependent: Fµν = ∂µAν − ∂νAµ − τσµνAσ
Constitutive Eqn1√g∂µ(
√gFµσ) = jσ − 1
2τσµνFµν
︸ ︷︷ ︸Machian Current?
• Quantities transformed from Lab → Rotating Frame
do obey these, but it does not provide insight to source
of interior fields in Barnett experiment where jσ = 0
X. Schiff Paradox (1939)
A). Lab Frame
• Net Charge:
Qa + Qb = 0
• Outside: ~E = 0
• Non-zero Dipole:
m = 12ωQ(a2 − b2)
Bz(r) = µ04π
ωQr3
(b2 − a2)
B). Lorentz Transf. by v = ωr
• B′z = γBz
• E′r = γωrBz
γ ≡ 1√1−ω2r2
c2
C). Rotating Frame
• No Current =⇒ B′z = 0 ?
• No net Charge =⇒ E′r = 0 ?
• Yet a + particle at rest at point r will expe-rience outward force in rotating frame?
XI. Partial Solution
A). Charges Don’t Cancel in Σ′
Charge in rotating frame: Q′a = 2πLσ′a
From Transformation: σ′a = σa
√1− ω2a2/c2
Lab Frame Charge Density: σa = Q/(2πaL)
Thus: Q′a = Q√
1− ω2a2/c2
Net Charge: ∆Q′ = Q′z −Q′b ' Qω2
2c2(b2 − a2)
B). Yields Nonzero Electric Field
Gauss Equation: 1r∂r(rE′r) + τ4
r4Er = ρ
Non Zero Field: E′r ' γ∆Q2πεorL = γQω2(b2−a2)
4πεoc2rL
Ouch, expected: E′r = γωrBz = µoγQω2(b2−a2)8πc2r2
So we are off by a factor of 2r/L ?
XII. Charge and Invariance
Did we violate charge conservation?
NO! Conservation applies IN a framenot BETWEEN frames
A). Spinning Mass Analogy
Dixon’s Invariant: p2 − S2/λ2 = (moc)2
Dynamic Mass: m2 = m2o
[1 + S2
(moλc)2
]
Radius of gyration λ, m ' mo + S2
2moλ2
B). New Charged Particle Analogy
• Current: j = em p
• Dipole Moment: U = e2m S
• Propose Invariant: j2 − 4U2
c2λ2 = (eo c)2
• Dynamic Charge: Q2 = Q2o
[1 + 4U2
(Qoλc)2
]
XIII. EM Rotational Relativity
A). Special Rotational Relativity
Carmelli (1986) proposes rotating transformation
m′ = γ(m− ω · S/c2)
S′ = γ(S −mωr2)
γ ≡ 1√1−ω2r2
c2
This leaves (m2 − S2/r2) invariant
Fundamental particles: want invariant mass and spin!
B). EM Analogy
Q′ = γ(Q− 2ω · U/c2)
U ′ = γ(U − 12Qωr2)
γ ≡ 1√1−ω2r2
c2
This leaves (Q2 − 4U2/r2) invariant. For fundamental
particles: want charge and dipole moment invariant!
C). Application
Consistent with our Schiff Paradox treatment,
U ′ = 0 , Q′a = Qa
√1− ω2a2/c2
XIV. Summary
• Propose: A Rotating Frame is equiv-
alent to a Rest Frame with Torsion
• For consistency, Electromagnetism
MUST couple to torsion
• Rotational EM Paradoxes are the
most problematic for attempting a
“theory of rotational relativity”
XV. References
1. Feynman, Lectures on Physics, (1975) p. 14-7.
2. Einstein, The Principle of Relativity, Chapter VII.
3. Adler, Bazin and Schiffer, Introduction to General Rela-
tivity, (1975) pp. 120-131.
4. J.F. Corum, “Relativistic Rotation and the Anholonomic Ob-
ject”, J.Math.Phys. 18, 770 (1977); “Relativistic Covariance and
Rotational Electrodynamics,” J.Math.Phys. 21, 2360 (1980).
5. P. Langevin, Comptes rendus 200, 48 (1935).
6. A. L. Kholmetskii, “One century later: Remarks on the Bar-
nett experiment,” Am. J. Phys. 71, 558-561 (2003).
7. L. Schiff, “A question in general relativity,” Proc. Natl. Acad.
Sci. USA 25, 391-395 (1939).
8. M. Carmeli, “Rotational Relativity Theory,” Int. J. Theor.
Phys., 25, No. 1, 89 (1986).
8. P. Franklin, “The Meaning of Rotation in the Special Theory
of Relativity,” Proc Natl. Acad. Sci. USA 8(9), 265-268 (1922).
9. H. Takeno, “On Relativistic Theory of Rotating Disk,” Prog.
Theor. Phys. 7(4), 367-376 (1952).
10. M.G. Trocheries, “Electrodynamics in a Rotating Frame of
Reference,” Phil. Mag. 40(310), 1143-1154 (1949).
11. B. Kursunoglu, “Spacetime on The Rotating Disk,” Proc.
Cambr. Phil. Soc. 47, 177 (1951).
12. H. Kleinert, “Nonabelian Bosonization as a Nonholonomic
Transformation from Flat to Curved Field Space,” Annals. Phys.
253, 121-176 (1997); “Nonholonomic Mapping Principle for Clas-
sical and Quantum Mechanics in Spaces with Curvature and Tor-
sion,” Gen. Rel. Grav. 32, 769 (2000).