A reformulation of Grassmann calculus is presented in terms of geometric algebra—a unified language for physics based on Clifford algebra. In this reformulation, Grassmann generators are replaced by vectors, so that every product of generators has a natural geometric interpretation. The calculus introduced by Berezin [TheMethodofSecondQuantization (Academic, New York, 1966)] is shown to be unnecessary, amounting to no more than an algebraic contraction. This approach is not only conceptually clearer, but it is also computationally more efficient, as demonstrated by treatments of the ‘‘Grauss’’ integral and the Grassmann Fourier Transform. The reformulation is applied to pseudoclassical mechanics [Ann. Phys. 104, 336 (1977)], where it is shown to lead to a new concept, the multivector Lagrangian. To illustrate this idea, the three‐dimensional Fermi oscillator is reformulated and solved, and its symmetry properties discussed. As a result, a new and highly compact formula for generating super‐Lie algebras is revealed. The paper ends with a discussion of quantization, outlining a new approach to fermionic path integrals.

1.
F. A. Berezin, The Method of Second Quantization (Academic Press, New York, 1966).
2.
P. G. O. Freund, Supersymmetry (Cambridge University, Cambridge, 1986).
3.
W. K.
Clifford
,
Am. J. Math.
1
,
350
(
1878
).
4.
H.
Grassmann
,
Math. Ann.
12
,
375
(
1877
).
5.
D. Hestenes, “A unified language for mathematics and physics,” in Clifford Algebras And Their Applications in Mathematical Physics, edited by J. S. R. Chisholm and A. K. Common (Reidel, Dordrecht, 1986), p. 1.
6.
D.
Hestenes
,
J. Math. Phys.
16
,
556
(
1975
).
7.
C. J. L. Doran, A. N. Lasenby, and S. F. Gull, “Grassmann mechanics, multivector derivatives and geometric algebra,” in Spinors, Twistors and Clifford Algebras, edited by Z. Oziewicz, A. Borowiec, and B. Jancewicz (Kluwer, Dordrecht, 1993).
8.
A. N. Lasenby, C. J. L. Doran, and S. F. Gull, “Two-spinors, twistors and supersymmetry in the spacetime algebra,” in Ref. 7.
9.
C. J. L. Doran, A. N. Lasenby, and S. F. Gull, “States and operators in the spacetime algebra,” to appear in Found. of Phys.
10.
A. N. Lasenby, C. J. L. Doran, and S. F. Gull, “A multivector derivative approach to Lagrangian field theory,” to appear in Found. Phys. 1993.
11.
R. Penrose and W. Rindler, Spinors and Space-Time, Volume I: Two-Spinor Calculus and Relativistic Fields (Cambridge University, Cambridge, 1984).
12.
C. J. L. Doran, D. Hestenes, F. Sommen, and N. van Acker, J. Math. Phys. (to be published).
13.
D. Hestenes and G. Sobczyk, Clifford Algebra to Geometric Calculus (Reidel, Dordrecht, 1984).
14.
S. F. Gull, A. N. Lasenby, and C. J. L. Doran, “Imaginary numbers are not real—the geometric algebra of spacetime,” to appear in Found. Phys.
15.
D.
Hestenes
,
Acta. Appl. Math.
23
,
65
(
1991
).
16.
R.
Ablamovicz
,
P.
Lounesto
, and
J.
Maks
,
Found. Phys.
21
,
735
(
1991
).
17.
I. W. Benn and R. W. Tucker, An Introduction to Spinors and Geometry (Hilger, London 1988).
18.
N.
Salingaros
,
J. Math. Phys.
23
,
1
(
1982
).
19.
D. Hestenes, New Foundations for Classical Mechanics (Reidel, Dordrecht, 1985).
20.
D.
Hestenes
,
Int. J. Theor. Phys.
25
,
581
(
1986
).
21.
F. A.
Berezin
and
M. S.
Marinov
,
Ann. Phys.
104
,
336
(
1977
).
22.
F. A. Berezin, Introduction to Superanalysis (Reidel, Dordrecht, 1987).
23.
B. de Witt, Supermanifolds (Cambridge University, Cambridge, 1984).
24.
R.
Coquereaux
,
A.
Jadczyk
, and
D.
Kastler
,
Rev. Math. Phys.
3
,
63
(
1991
).
25.
A.
Connes
and
J.
Lott
,
Nucl. Phys. B Proc. Suppl.
18
,
29
(
1990
).
26.
P. Lounesto (private communication).
27.
G. C.
Sherry
,
Found. Phys. Lett.
2
,
591
(
1989
).
28.
G. C.
Sherry
,
Found. Phys. Lett.
3
,
267
(
1990
).
29.
S. F. Gull, A. N. Lasenby, and C. J. L. Doran, “Electron paths, tunelling and diffraction in the spacetime algebra,” to appear in Found. Phys.
30.
R.
Casalbuoni
,
Nuovo Cimento A
33
,
389
(
1976
).
31.
A. O.
Barut
and
N.
Zanghi
,
Phys. Rev. Lett.
52
,
2009
(
1984
).
32.
L.
Brink
,
S.
Deser
,
B.
Zumino
,
P.
di Vecchia
, and
P.
Howe
,
Phys. Lett. B
64
,
435
(
1976
).
33.
J. F. Cornwell, Group Theory in Physics III (Academic, New York, 1989).
34.
M. Scheunert, “Representations of Lie superalgebras, an introduction,” in Differential Geometrical Methods in Theoretical Physics, edited by K. Bleuler and M. Werner (Kluwer, Dordrecht, 1988), p. 441.
35.
P.
Lounesto
,
Found. Phys.
11
,
721
(
1981
).
36.
J.
Keller
and
S.
Rodriguez-Romo
,
Int. J. Theor. Phys.
30
,
185
(
1991
).
37.
Z.
Oziewicz
,
A. K.
Kwasniewski
, and
P.
Morawiec
,
J. Math. Phys.
25
,
2031
(
1984
).
38.
D.
Hestenes
,
J. Math. Phys.
15
,
1778
(
1974
).
39.
F. Rohrlich, Classical Charged Particles (Addison-Wesley, Reading, MA, 1965).
40.
A. T.
Ogielski
and
J.
Sobczyk
,
J. Math. Phys.
22
,
2060
(
1981
).
41.
R. P. Feynman and A. R. Hibbs, Quantum Mechanics and Path Integrals (McGraw-Hill, New York, 1965).
This content is only available via PDF.
You do not currently have access to this content.