Physlib.Relativity.LorentzGroup.Proper
20 declarations
Let denote the Lorentz group acting on a -dimensional Minkowski space. For any element , the determinant of its matrix representation is either or . That is,
Discrete topology on
#instTopologicalSpaceMultiplicativeZModOfNatNatThe definition provides a topological space structure on the group (the cyclic group of order 2), where the topology assigned is the discrete topology.
is a discrete space
#instDiscreteTopologyMultiplicativeZModOfNatNatThe topological space defined on the group (the cyclic group of order 2) is a discrete space.
is a topological group
#instIsTopologicalGroupMultiplicativeZModOfNatNatThe cyclic group of order 2, , is a topological group when equipped with the discrete topology. This implies that the group multiplication and inversion operations are continuous maps.
Continuous map from to
#coeForℤ₂The function is a continuous map , where the domain is a subset of the real numbers and is the cyclic group of order 2. The map is defined such that is the identity element of (corresponding to ) and is the non-identity element of (corresponding to ).
Continuous determinant map
#detContinuousThe continuous map from the Lorentz group to the cyclic group of order 2. For a Lorentz matrix , it maps the determinant to the corresponding element in , where corresponds to the identity element and corresponds to the non-identity element.
For any element in the Lorentz group , the continuous determinant map evaluates to the identity element of if and only if the determinant of the matrix is .
For any element in the Lorentz group acting on -dimensional Minkowski space, the continuous determinant map evaluates to the non-identity element of if and only if the determinant of the matrix representation of is .
For any elements and in the Lorentz group , the values of the continuous determinant map are equal if and only if the determinants of their matrix representations are equal. That is,
Determinant representation
#detRepThe group homomorphism from the Lorentz group to the cyclic group of order 2. For any Lorentz transformation , the map sends to its determinant , represented as an element of . Specifically, a determinant of corresponds to the identity element of , and a determinant of corresponds to the non-identity element.
The determinant representation is continuous
#detRep_continuousLet be the -dimensional Lorentz group and be the cyclic group of order 2 equipped with the discrete topology. The determinant representation , which maps a Lorentz transformation to its determinant represented in , is continuous.
For any two Lorentz transformations and in the Lorentz group (the group of linear transformations preserving the Lorentz metric in dimensions), if belongs to the same connected component as , then their determinants are equal: .
for in the same connected component as
#detRep_on_connected_componentLet be the Lorentz group in dimensions. For any two Lorentz transformations , if belongs to the same connected component as , then their images under the determinant representation are equal, i.e., .
for Lorentz transformations joined by a path
#det_of_joinedFor any two Lorentz transformations and in the -dimensional Lorentz group, if and are joined by a path, then their determinants are equal: .
Proper Lorentz transformation ()
#IsProperFor a Lorentz transformation in the Lorentz group of dimension , the property holds if the determinant of the matrix representation of is equal to , denoted as .
Decidability of the proper Lorentz transformation predicate ()
#instDecidablePredElemMatrixSumFinOfNatNatRealIsProperFor a Lorentz transformation in the Lorentz group of dimension , the property , which is defined by the condition that the determinant of the matrix representation of is equal to (), is a decidable predicate.
Product of proper Lorentz transformations is proper
#isProper_mulFor any two Lorentz transformations and in the Lorentz group of dimension , if and are proper transformations (meaning and ), then their product is also a proper Lorentz transformation.
For any Lorentz transformation in the Lorentz group of dimension , is a proper Lorentz transformation () if and only if its image under the determinant representation is the identity element .
The Identity Lorentz Transformation is Proper
#isProper_idThe identity element of the Lorentz group in dimensions is a proper Lorentz transformation (i.e., its determinant is equal to ).
for Transformations in the Same Connected Component
#isProper_on_connected_componentFor any two Lorentz transformations and in the Lorentz group of dimension , if belongs to the same connected component as , then is a proper Lorentz transformation if and only if is a proper Lorentz transformation. A Lorentz transformation is called proper if its determinant is equal to .
