Learning path
Each declaration appears after its prerequisites.
- approx_hom_pfr Let $G, G'$ be finite abelian $2$-groups
- dual_iso Non canonical isomorphism between a finite 2-torsion group and its dual into
ZMod 2 - ProbabilityTheory.iIndepFun.sum_elim For Mathlib?
- mutual_information_le Documented declaration: mutual_information_le
- hmeas2 (Mantas) this times out in the proof below
- I₃_eq The quantity
I_3 = I[V:W|S]is equal toI_2 - sum_condMutual_le
I[U : V | S] + I[V : W | S] + I[W : U | S]is less than or equal to6 * η * k - (1 - 5 * η) / (1 - η) * (2 * η * k - I₁) - sum_dist_diff_le $$ \sum_{i=1}^2 \sum_{A\in\{U,V,W\}} \big(d[X^0_i;A|S] - d[X^0_i;X_i]\big)$$ is less than or equal to $$ \leq (6 - 3\eta) k + 3(2 \eta k - I_1).$$
- sum_uvw_eq_zero
U + V + W = 0 - construct_good_prelim Documented declaration: construct_good_prelim
- construct_good Documented declaration: construct_good
- tau_strictly_decreases_aux If
d[X₁ ; X₂] > 0then there areG-valued random variablesX₁', X₂'such that Phrased in the contrapositive form for convenience of proof - tau_strictly_decreases If $d[X_1;X_2] > 0$ then there are $G$-valued random variables $X'_1, X'_2$ such that $\tau[X'_1;X'_2] < \tau[X_1;X_2]$
- rdist_of_indep_eq_sum_fibre Documented declaration: rdist_of_indep_eq_sum_fibre
- rdist_of_hom_le \[d[X;Y]\geq d[\pi(X);\pi(Y)].\]
- sum_of_rdist_eq_step_condRuzsaDist The conditional Ruzsa Distance step of
sum_of_rdist_eq - sum_of_rdist_eq_step_condMutualInfo The conditional mutual information step of
sum_of_rdist_eq - sum_of_rdist_eq Let $Y_1,Y_2,Y_3$ and $Y_4$ be independent $G$-valued random variables
- sum_of_rdist_eq_char_2 Let $Y_1,Y_2,Y_3$ and $Y_4$ be independent $G$-valued random variables
- rdist_add_rdist_add_condMutual_eq Documented declaration: rdist_add_rdist_add_condMutual_eq
- rdist_of_sums_ge The distance $d[X_1+\tilde X_2; X_2+\tilde X_1]$ is at least $$k - \eta (d[X^0_1; X_1+\tilde X_2] - d[X^0_1; X_1]) - \eta (d[X^0_2; X_2+\tilde X_1] - d[X^0_2; X_2]).$$
- condRuzsaDist_of_sums_ge Documented declaration: condRuzsaDist_of_sums_ge
- diff_rdist_le_1
d[X₀₁ # X₁ + X₂'] - d[X₀₁ # X₁] ≤ k/2 + H[X₂]/4 - H[X₁]/4 - diff_rdist_le_2 $$ d[X^0_2;X_2+\tilde X_1] - d[X^0_2; X_2] \leq \tfrac{1}{2} k + \tfrac{1}{4} \mathbb{H}[X_1] - \tfrac{1}{4} \mathbb{H}[X_2].$$
- diff_rdist_le_3 $$ d[X_1^0;X_1|X_1+\tilde X_2] - d[X_1^0;X_1] \leq \tfrac{1}{2} k + \tfrac{1}{4} \mathbb{H}[X_1] - \tfrac{1}{4} \mathbb{H}[X_2].$$
- diff_rdist_le_4 $$ d[X_2^0; X_2|X_2+\tilde X_1] - d[X_2^0; X_2] \leq \tfrac{1}{2}k + \tfrac{1}{4} \mathbb{H}[X_2] - \tfrac{1}{4} \mathbb{H}[X_1].$$
- first_estimate We have $I_1 \leq 2 \eta k$
- ent_ofsum_le $$\mathbb{H}[X_1+X_2+\tilde X_1+\tilde X_2] \le \tfrac{1}{2} \mathbb{H}[X_1]+\tfrac{1}{2} \mathbb{H}[X_2] + (2 + \eta) k - I_1.$$
- AffineSpace.finrank The dimension of the affine span over
ℤof a subset of an additive group - ProbabilityTheory.IndepFun.identDistrib_cond If
Ais independent fromB, then conditioning on an event given byBdoes not change the distribution ofA - ProbabilityTheory.IndepFun.cond_left If
Ais independent ofB, then they remain independent when conditioning on an event of the formA ∈ sof positive probability - ProbabilityTheory.IndepFun.cond_right If
Ais independent ofB, then they remain independent when conditioning on an event of the formB ∈ tof positive probability - ProbabilityTheory.IndepFun.cond If
Ais independent ofB, then they remain independent when conditioning on an event of the formA ∈ s ∩ B ∈ tof positive probability - ProbabilityTheory.CondIndepFun The assertion that
fandgare conditionally independent relative toh - ProbabilityTheory.CondIndepFun.comp_right Composing independent functions with a measurable embedding of conull range gives independent functions
- ProbabilityTheory.condIndep_copies For
X, Yrandom variables, there exist conditionally independent trialsX_1, X_2, Y' - ProbabilityTheory.condIndep_copies' For
X, Yrandom variables, there exist conditionally independent trialsX₁, X₂, Y' - ProbabilityTheory.entropy_def Entropy of a random variable agrees with entropy of its distribution
- ProbabilityTheory.entropy_eq_kernel_entropy Entropy of a random variable is also the kernel entropy of the distribution over a Dirac mass
- ProbabilityTheory.entropy_zero_measure Any variable on a zero measure space has zero entropy
- ProbabilityTheory.entropy_congr Two variables that agree almost everywhere, have the same entropy
- ProbabilityTheory.entropy_nonneg Entropy is always non-negative
- ProbabilityTheory.IdentDistrib.entropy_congr Two variables that have the same distribution, have the same entropy
- ProbabilityTheory.entropy_le_log_card Entropy is at most the logarithm of the cardinality of the range
- ProbabilityTheory.entropy_le_log_card_of_mem Entropy is at most the logarithm of the cardinality of a set in which X almost surely takes values in
- ProbabilityTheory.entropy_le_log_card_of_mem_finite Entropy is at most the logarithm of the cardinality of a set in which X almost surely takes values in
- ProbabilityTheory.entropy_eq_sum
H[X] = ∑ₛ P[X=s] log 1 / P[X=s] - ProbabilityTheory.entropy_cond_eq_sum
H[X | Y=y] = ∑_s P[X=s | Y=y] log 1/(P[X=s | Y=y]) - ProbabilityTheory.entropy_comp_of_injective If
X,YareS-valued andT-valued random variables, andY = f(X)for some injectionf : S \to T, thenH[Y] = H[X] - ProbabilityTheory.entropy_const The entropy of any constant is zero
- ProbabilityTheory.IsUniform.entropy_eq If
Xis uniformly distributed onH, thenH[X] = log |H| - ProbabilityTheory.IsUniform.entropy_eq' Variant of
IsUniform.entropy_congrwhereHis a finiteSetrather thanFinset - ProbabilityTheory.entropy_eq_log_card If
XisS-valued random variable, thenH[X] = log |S|if and only ifXis uniformly distributed - ProbabilityTheory.prob_ge_exp_neg_entropy If
Xis anS-valued random variable, then there existss ∈ Ssuch thatP[X = s] ≥ \exp(- H[X]) - ProbabilityTheory.prob_ge_exp_neg_entropy' If
Xis anS-valued random variable, then there existss ∈ Ssuch thatP[X=s] ≥ \exp(-H[X]) - ProbabilityTheory.const_of_nonpos_entropy If
Xis anS-valued random variable of non-positive entropy, thenXis almost surely constant - ProbabilityTheory.entropy_prod_comp
H[X, f(X)] = H[X] - ProbabilityTheory.entropy_comm
H[X, Y] = H[Y, X] - ProbabilityTheory.entropy_assoc
H[(X, Y), Z] = H[X, (Y, Z)] - ProbabilityTheory.condEntropy_eq_kernel_entropy Conditional entropy of a random variable is equal to the entropy of its conditional kernel
- ProbabilityTheory.condEntropy_zero_measure Any random variable on a zero measure space has zero conditional entropy
- ProbabilityTheory.condEntropy_nonneg Conditional entropy is non-negative
- ProbabilityTheory.condEntropy_le_log_card Conditional entropy is at most the logarithm of the cardinality of the range
- ProbabilityTheory.condEntropy_eq_sum
H[X|Y] = ∑_y P[Y=y] H[X|Y=y] - ProbabilityTheory.condEntropy_eq_sum_fintype
H[X|Y] = ∑_y P[Y=y] H[X|Y=y] - ProbabilityTheory.condEntropy_eq_sum_sum
H[X|Y] = ∑_y ∑_x P[Y=y] P[X=x|Y=y] log ⧸(P[X=x|Y=y])$ - ProbabilityTheory.condEntropy_eq_sum_sum_fintype
H[X|Y] = ∑_y ∑_x P[Y=y] P[X=x|Y=y] log ⧸(P[X=x|Y=y])$ - ProbabilityTheory.condEntropy_eq_sum_prod Same as previous lemma, but with a sum over a product space rather than a double sum
- ProbabilityTheory.condEntropy_of_injective If
X : Ω → S,Y : Ω → Tare random variables, andf : T × S → Uis injective for each fixedt ∈ T, thenH[f(Y, X) | Y] = H[X | Y] - ProbabilityTheory.condEntropy_comp_of_injective A weaker version of the above lemma in which
fis independent ofY - ProbabilityTheory.condEntropy_comm
H[X, Y| Z] = H[Y, X| Z] - ProbabilityTheory.chain_rule' One form of the chain rule :
H[X, Y] = H[X] + H[Y | X] - ProbabilityTheory.chain_rule Another form of the chain rule :
H[X, Y] = H[Y] + H[X | Y] - ProbabilityTheory.chain_rule'' Another form of the chain rule :
H[X | Y] = H[X, Y] - H[Y] - ProbabilityTheory.IdentDistrib.condEntropy_eq Two pairs of variables that have the same joint distribution, have the same conditional entropy
- ProbabilityTheory.condEntropy_of_injective' If
X : Ω → SandY : Ω → Tare random variables, andf : T → Uis an injection thenH[X | f(Y)] = H[X | Y] - ProbabilityTheory.condEntropy_comp_self
H[X | f(X)] = H[X] - H[f(X)] - ProbabilityTheory.cond_chain_rule' If
X : Ω → S,Y : Ω → T,Z : Ω → Uare random variables, thenH[X, Y | Z] = H[X | Z] + H[Y|X, Z] - ProbabilityTheory.cond_chain_rule
H[X, Y | Z] = H[Y | Z] + H[X | Y, Z] - ProbabilityTheory.entropy_comp_le Data-processing inequality for the entropy:
H[f(X)] ≤ H[X] - ProbabilityTheory.entropy_of_comp_eq_of_comp A Schroder-Bernstein type theorem for entropy : if two random variables are functions of each other, then they have the same entropy
- ProbabilityTheory.IdentDistrib.mutualInfo_eq Substituting variables for ones with the same distributions doesn't change the mutual information
- ProbabilityTheory.mutualInfo_nonneg Mutual information is non-negative
- ProbabilityTheory.entropy_pair_le_add Subadditivity of entropy
- ProbabilityTheory.mutualInfo_eq_zero
I[X : Y] = 0iffX, Yare independent - ProbabilityTheory.mutualInfo_const The mutual information with a constant is always zero
- ProbabilityTheory.entropy_pair_eq_add
H[X, Y] = H[X] + H[Y]if and only ifX, Yare independent - ProbabilityTheory.mutualInfo_comm
I[X : Y] = I[Y : X] - ProbabilityTheory.mutualInfo_eq_entropy_sub_condEntropy
I[X : Y] = H[X] - H[X|Y] - ProbabilityTheory.mutualInfo_eq_entropy_sub_condEntropy'
I[X : Y] = H[Y] - H[Y | X] - ProbabilityTheory.entropy_sub_mutualInfo_eq_condEntropy
H[X] - I[X : Y] = H[X | Y] - ProbabilityTheory.entropy_sub_mutualInfo_eq_condEntropy'
H[Y] - I[X : Y] = H[Y | X] - ProbabilityTheory.condMutualInfo_eq_kernel_mutualInfo The conditional mutual information agrees with the information of the conditional kernel
- ProbabilityTheory.condMutualInfo_eq_sum' A variant of
condMutualInfo_eq_sumwhenZhas finite codomain - ProbabilityTheory.condMutualInfo_nonneg Conditional information is non-nonegative
- ProbabilityTheory.condMutualInfo_comm
I[X : Y | Z] = I[Y : X | Z] - ProbabilityTheory.condMutualInfo_eq
I[X : Y| Z] = H[X| Z] + H[Y| Z] - H[X, Y| Z] - ProbabilityTheory.condMutualInfo_eq'
I[X : Y| Z] = H[X| Z] - H[X|Y, Z] - ProbabilityTheory.condMutualInfo_of_inj_map If
f(Z, X)is injective for each fixedZ, thenI[f(Z, X) : Y| Z] = I[X : Y| Z] - ProbabilityTheory.condMutualInfo_eq_zero
I[X : Y| Z]=0iffX, Yare conditionally independent overZ - ProbabilityTheory.ent_of_cond_indep If
X, Yare conditionally independent overZ, thenH[X, Y, Z] = H[X, Z] + H[Y, Z] - H[Z] - ProbabilityTheory.entropy_sub_condEntropy
H[X] - H[X|Y] = I[X : Y] - ProbabilityTheory.condEntropy_le_entropy
H[X | Y] ≤ H[X] - ProbabilityTheory.entropy_submodular
H[X | Y, Z] ≤ H[X | Z] - ProbabilityTheory.condEntropy_comp_ge Data-processing inequality for the conditional entropy:
H[Y|f(X)] ≥ H[Y|X]To upgrade this to equality, seecondEntropy_of_injective' - ProbabilityTheory.entropy_triple_add_entropy_le The submodularity inequality:
H[X, Y, Z] + H[Z] ≤ H[X, Z] + H[Y, Z] - ProbabilityTheory.mutual_comp_le Let
X, Ybe random variables - ProbabilityTheory.mutual_comp_comp_le Let
X, Ybe random variables - ProbabilityTheory.condMutual_comp_comp_le Let
X, Y, Z - ProbabilityTheory.entropy_mul_right
H[X, X + Y] = H[X, Y] - ProbabilityTheory.entropy_mul_right'
H[X, Y + X] = H[X, Y] - ProbabilityTheory.entropy_mul_left
H[Y + X, Y] = H[X, Y] - ProbabilityTheory.entropy_mul_left'
H[X + Y, Y] = H[X, Y] - ProbabilityTheory.entropy_inv_right
H[X, -Y] = H[X, Y] - ProbabilityTheory.entropy_inv_left
H[-X, Y] = H[X, Y] - ProbabilityTheory.entropy_div_right
H[X, X - Y] = H[X, Y] - ProbabilityTheory.entropy_div_right'
H[X, Y - X] = H[X, Y] - ProbabilityTheory.entropy_div_left
H[Y - X, Y] = H[X, Y] - ProbabilityTheory.entropy_div_left'
H[X - Y, Y] = H[X, Y] - ProbabilityTheory.entropy_inv If
XisG-valued, thenH[-X]=H[X] - ProbabilityTheory.entropy_div_comm
H[X - Y] = H[Y - X] - ProbabilityTheory.max_condEntropy_sub_condMutualInfo_le_condEntropy_div
max(H[X | Z], H[Y | Z]) - I[X : Y | Z] ≤ H[X - Y | Z] - ProbabilityTheory.condEntropy_mul_left
H[Y + X | Y] = H[X | Y] - ProbabilityTheory.condEntropy_mul_right
H[X + Y | Y] = H[X | Y] - ProbabilityTheory.condEntropy_div_left
H[Y - X | Y] = H[X | Y] - ProbabilityTheory.condEntropy_div_right
H[X - Y | Y] = H[X | Y] - ProbabilityTheory.mutualInfo_mul_right
I[X : X + Y] = H[X + Y] - H[Y]iffX, Yare independent - ProbabilityTheory.entropy_sub_mutualInfo_le_entropy_mul
H[X] - I[X : Y] ≤ H[X + Y] - ProbabilityTheory.entropy_sub_mutualInfo_le_entropy_mul'
H[Y] - I[X : Y] ≤ H[X + Y] - ProbabilityTheory.entropy_sub_mutualInfo_le_entropy_div
H[X] - I[X : Y] ≤ H[X - Y] - ProbabilityTheory.entropy_sub_mutualInfo_le_entropy_div'
H[Y] - I[X : Y] ≤ H[X - Y] - ProbabilityTheory.max_entropy_sub_mutualInfo_le_entropy_mul
max(H[X], H[Y]) - I[X : Y] ≤ H[X + Y] - ProbabilityTheory.max_entropy_sub_mutualInfo_le_entropy_div
max(H[X], H[Y]) - I[X : Y] ≤ H[X - Y] - ProbabilityTheory.max_condEntropy_sub_condMutualInfo_le_condEntropy_mul
max(H[X | Z], H[Y | Z]) - I[X : Y | Z] ≤ H[X + Y | Z] - ProbabilityTheory.max_entropy_le_entropy_mul If
X, Yare independent, thenmax(H[X], H[Y]) ≤ H[X + Y] - ProbabilityTheory.max_entropy_le_entropy_div If
X, Yare independent, thenmax(H[X], H[Y]) ≤ H[X - Y] - ProbabilityTheory.Kernel.finiteKernelSupport_of_const Constant kernels with finite support, have finite kernel support
- ProbabilityTheory.Kernel.finiteSupport_of_compProd' Composing a finitely supported measure with a finitely supported kernel gives a finitely supported kernel
- ProbabilityTheory.Kernel.entropy_snd_compProd_deterministic_of_injective entropy_map_of_injective is a special case of this (see def of map)
- ProbabilityTheory.Kernel.entropy_map_le Data-processing inequality for the kernel entropy
- ProbabilityTheory.Kernel.entropy_snd_sub_mutualInfo_le_entropy_map_of_injective TODO: extract lemma(s) from this:
- ProbabilityTheory.Kernel.entropy_submodular_compProd from kernel (T × S × U) V ; Measure (T × S × U) to kernel (T × S) V ; Measure (T × S)
- ProbabilityTheory.Kernel.entropy_compProd_triple_add_entropy_le $$ H[X,Y,Z] + H[X] \leq H[Z,X] + H[Y,X].$$
- ProbabilityTheory.Kernel.entropy_triple_add_entropy_le' The submodularity inequality: $$ H[X,Y,Z] + H[X] \leq H[X,Z] + H[X,Y].$$
- ProbabilityTheory.Kernel.entropy_triple_add_entropy_le The submodularity inequality: $$ H[X,Y,Z] + H[Z] \leq H[X,Z] + H[Y,Z].$$
- ProbabilityTheory.Kernel.ent_of_diff_le The improved entropic Ruzsa triangle inequality
- ProbabilityTheory.FiniteSupport A measure has finite support if there exists a finite set whose complement has zero measure
- ProbabilityTheory.FiniteEntropy TODO: replace FiniteSupport hypotheses ∈ these files with FiniteEntropy hypotheses
- ProbabilityTheory.full_measure_of_finiteRange duplicate of
FiniteRange.null_of_compl - ProbabilityTheory.integrable_of_finiteSupport Every function is integrable against a finite measure with finite support
- ProbabilityTheory.Measure.ext_iff_singleton_finiteSupport This generalizes Measure.ext_iff_singleton ∈ MeasureReal
- ProbabilityTheory.measureEntropy_le_card_aux Auxiliary lemma for
measureEntropy_le_log_card_of_mem, which removes the probability measure assumption - ProbabilityTheory.entropy_of_uniformOn The entropy of a uniform measure is the log of the cardinality of its support
- ProbabilityTheory.measureEntropy_prod An ambitious goal would be to replace FiniteSupport with finite entropy
- ProbabilityTheory.measureMutualInfo_nonneg_aux An ambitious goal would be to replace FiniteSupport with finite entropy
- continuous_measureEntropy_probabilityMeasure Entropy depends continuously on the measure
- rdist
- rdist_def Explicit formula for the Ruzsa distance
- rdist_eq_rdistm Ruzsa distance of random variables equals Ruzsa distance of the kernels
- continuous_rdist_restrict_probabilityMeasure Ruzsa distance depends continuously on the measure
- rdist_eq_rdist_id_map Ruzsa distance between random variables equals Ruzsa distance between their distributions
- continuous_rdist_restrict_probabilityMeasure₁' Ruzsa distance depends continuously on the second measure
- ProbabilityTheory.IdentDistrib.rdist_congr If
X', Y'are copies ofX, Yrespectively thend[X' ; Y'] = d[X ; Y] - ProbabilityTheory.IdentDistrib.rdist_congr_left If
X', Y'are copies ofX, Yrespectively thend[X' ; Y'] = d[X ; Y] - ProbabilityTheory.IdentDistrib.rdist_congr_right If
X', Y'are copies ofX, Yrespectively thend[X' ; Y'] = d[X ; Y] - ProbabilityTheory.IndepFun.rdist_eq If
X, Yare independentG-random variables thend[X ; Y] = H[X - Y] - H[X]/2 - H[Y]/2 - rdist_le_avg_ent
d[X ; Y] ≤ H[X]/2 + H[Y]/2 - rdist_of_inj Applying an injective homomorphism does not affect Ruzsa distance
- rdist_zero_eq_half_ent
d[X ; 0] = H[X] / 2 - rdist_symm
d[X ; Y] = d[Y ; X] - continuous_rdist_restrict_probabilityMeasure₁_left Ruzsa distance depends continuously on the first measure
- diff_ent_le_rdist
|H[X] - H[Y]| ≤ 2 d[X ; Y] - diff_ent_le_rdist'
H[X - Y] - H[X] ≤ 2d[X ; Y] - diff_ent_le_rdist''
H[X - Y] - H[Y] ≤ 2d[X ; Y] - rdist_nonneg
d[X ; Y] ≥ 0 - ent_of_proj_le Documented declaration: ent_of_proj_le
- rdist_add_const Adding a constant to a random variable does not change the Rusza distance
- rdist_add_const' A variant of
rdist_add_constwhere one adds constants to both variables - ent_of_diff_le The improved entropic Ruzsa triangle inequality
- rdist_triangle The entropic Ruzsa triangle inequality
- condRuzsaDist_eq_sum' Explicit formula for conditional Ruzsa distance $d[X|Z; Y|W]$ in a fintype
- condRuzsaDist_eq_sum Explicit formula for conditional Ruzsa distance $d[X|Z; Y|W]$
- condRuzsaDist_symm $$ d[X|Z; Y|W] = d[Y|W; X|Z]$$
- condRuzsaDist'_def Conditional Ruzsa distance equals Ruzsa distance of associated kernels
- condRuzsaDist'_eq_sum Explicit formula for conditional Ruzsa distance
d[X ; Y | W] - condRuzsaDist'_eq_sum' Alternate formula for conditional Ruzsa distance
d[X ; Y | W]when T is a Fintype - condRuzsaDist'_prod_eq_sum' Version of
condRuzsaDist'_prod_eq_sumwhenWhas finite codomain - condRuzsaDist'_eq_integral Explicit formula for conditional Ruzsa distance
d[X ; Y | W], in integral form - condRuzsaDist_of_const Conditioning by a constant does not affect Ruzsa distance
- condRuzsaDist_of_indep If
$(X,Z)$and$(Y,W)$are independent, thend[X | Z ; Y | W] = H[X'- Y' | Z', W'] - H[X'|Z']/2 - H[Y'|W']/2 - condRuzsaDist'_of_indep Formula for conditional Ruzsa distance for independent sets of variables
- condRuzsaDist_of_copy The conditional Ruzsa distance is unchanged if the sets of random variables are replaced with copies
- kaimanovich_vershik The Kaimanovich-Vershik inequality
- kaimanovich_vershik' A version of the Kaimanovich-Vershik inequality with some variables negated
- ent_bsg The entropic Balog-Szemerédi-Gowers inequality
- condRuzsaDist_le Suppose that $(X, Z)$ and $(Y, W)$ are random variables, where $X, Y$ take values in an abelian group
- condRuzsaDist_diff_le Let
X, Y, Zbe random variables taking values in some abelian group, and withY, Zindependent - ProbabilityTheory.setRuzsaDist The Ruzsa distance between two subsets
A,Bof a groupGis defined to be the Ruzsa distance between their uniform probability distributions - ProbabilityTheory.setRuzsaDist_eq_rdist Relating Ruzsa distance between sets to Ruzsa distance between random variables
- ProbabilityTheory.setRuzsaDist_nonneg Ruzsa distance between sets is nonnegative
- ProbabilityTheory.setRuzsaDist_symm Ruzsa distance between sets is symmetric
- ProbabilityTheory.setRuzsaDist_triangle Ruzsa distance between sets obeys the triangle inequality
- ProbabilityTheory.setRuzsaDist_add_const Ruzsa distance between sets is translation invariant
- ProbabilityTheory.setRuzsaDist_of_inj Ruzsa distance between sets is preserved by injective homomorphisms
- ProbabilityTheory.setRuzsaDist_le Ruzsa distance between sets is controlled by the doubling constant
- ProbabilityTheory.sum_meas_smul_cond_fiber' Documented declaration: sum_meas_smul_cond_fiber'
- FiniteRange The property of having a finite range
- FiniteRange.fintype fintype structure on the range of a finite range map
- FiniteRange.toFinset The range of a finite range map, as a finset
- finiteRange_of_finset Functions ranging in a Finset have finite range
- FiniteRange.mul The sum of functions of finite range, has finite range
- FiniteRange.mul' The sum of functions of finite range, has finite range
- FiniteRange.div The difference of functions of finite range, has finite range
- FiniteRange.div' The sum of functions of finite range, has finite range
- FiniteRange.inv The negation of a function of finite range, has finite range
- FiniteRange.inv' The sum of functions of finite range, has finite range
- FiniteRange.zpow The multiple of a function of finite range by a constant, has finite range
- FiniteRange.zpow' The multiple of a function of finite range by a constant, has finite range
- FiniteRange.finprod The sum of a finite number of functions with finite range, has finite range
- ProbabilityTheory.identDistrib_of_finiteRange If
Xhas identical distribution toX₀, andX₀has finite range, thenXis almost everywhere equivalent to a random variable of finite range - ProbabilityTheory.independent_copies_finiteRange A version of
independent_copiesthat guarantees that the copies haveFiniteRangeif the original variables do - ProbabilityTheory.independent_copies3_nondep_finiteRange A version of
independent_copies3_nondepthat guarantees that the copies haveFiniteRangeif the original variables do - ProbabilityTheory.independent_copies4_nondep_finiteRange A version of
independent_copies4_nondepthat guarantees that the copies haveFiniteRangeif the original variables do - ProbabilityTheory.independent_copies'_finiteRange A version of
independent_copies'that guarantees that the copies haveFiniteRangeif the original variables do - ProbabilityTheory.iIndepFun.apply_two_last If
(Z₁, Z₂, Z₃, Z₄)are independent, so are(Z₁, Z₂, φ Z₃ Z₄)for any measurableφ - prod The pair of two random variables
- ProbabilityTheory.IsUniform The assertion that the law of $X$ is the uniform probability measure on a finite set $H$
- ProbabilityTheory.exists_isUniform Uniform distributions exist
- ProbabilityTheory.IsUniform.comp The image of a uniform random variable under an injective map is uniform on the image
- ProbabilityTheory.exists_isUniform_measureSpace Uniform distributions exist, version giving a measure space
- ProbabilityTheory.exists_isUniform_measureSpace' Uniform distributions exist, version with a Finite set rather than a Finset and giving a measure space
- ProbabilityTheory.IsUniform.ae_mem A uniform random variable on H almost surely takes values in H
- ProbabilityTheory.IsUniform.nonempty Uniform random variables only exist for non-empty sets H
- ProbabilityTheory.IsUniform.measure_preimage_of_nmem A "unit test" for the definition of uniform distribution
- ProbabilityTheory.IsUniform.measureReal_preimage_of_nmem Another "unit test" for the definition of uniform distribution
- ProbabilityTheory.IsUniform.measure_preimage_of_mem A "unit test" for the definition of uniform distribution
- ProbabilityTheory.IsUniform.measureReal_preimage_of_mem A "unit test" for the definition of uniform distribution
- ProbabilityTheory.IsUniform.measure_preimage $\mathbb{P}(U_H \in H') = \dfrac{|H' \cap H|}{|H|}$
- ProbabilityTheory.IsUniform.measureReal_preimage $\mathbb{P}(U_H \in H') = \dfrac{|H' \cap H|}{|H|}$
- ProbabilityTheory.IsUniform.of_identDistrib A copy of a uniform random variable is also uniform
- ProbabilityTheory.IsUniform.measure_preimage_ne_zero $\mathbb{P}(U_H \in H') \neq 0$ if $H'$ intersects $H$ and the measure is non-zero
- ProbabilityTheory.IsUniform.restrict If $X$ is uniform w.r.t
- ProbabilityTheory.isUniform_iff_map_eq_uniformOn A random variable is uniform iff its distribution is
- hahn_banach Let $H_0$ be a subgroup of $G$
- goursat Let $H$ be a subgroup of $G \times G'$
- homomorphism_pfr Homomorphism PFR after goursat
- symmGroup The symmetry group Sym of $X$: the set of all $h ∈ G$ such that $X + h$ has an identical distribution to $X$
- sub_mem_symmGroup If $d[X ;X]=0$, and $x,y \in G$ are such that $P[X=x], P[X=y]>0$, then $x-y \in \mathrm{Sym}[X]$
- isUniform_sub_const_of_rdist_eq_zero If
d[X # X] = 0, thenX - x₀is the uniform distribution on the subgroup ofGstabilizing the distribution ofX, for anyx₀of positive probability - exists_isUniform_of_rdist_self_eq_zero If $d[X ;X]=0$, then there exists a subgroup $H \leq G$ such that $d[X ;U_H] = 0$
- exists_isUniform_of_rdist_eq_zero If $d[X_1;X_2]=0$, then there exists a subgroup $H \leq G$ such that $d[X_1;U_H] = d[X_2;U_H] = 0$
- gen_ineq_00 Let
Z₁, Z₂, Z₃, Z₄be independentG-valued random variables, and letYbe anotherG-valued random variable - gen_ineq_01 Other version of
gen_ineq_00, in which we switch to the complement in the second term - gen_ineq_10 Other version of
gen_ineq_00, in which we switch to the complement in the first term - construct_good_prelim' Documented declaration: construct_good_prelim'
- construct_good_improved' In fact $k$ is at most $$ \delta + \frac{\eta}{6} \sum_{i=1}^2 \sum_{1 \leq j,l \leq 3; j \neq l} (d[X^0_i;T_j|T_l] - d[X^0_i; X_i]).$$
- construct_good_improved'' Rephrase
construct_good_improved'with an explicit probability measure, as we will apply it to (varying) conditional measures - averaged_construct_good Documented declaration: averaged_construct_good
- tau_strictly_decreases_aux' Suppose $0 < \eta < 1/8$
- tau_minimizer_exists_rdist_eq_zero For
p.η ≤ 1/8, there exist τ-minimizersX₁, X₂at zero Rusza distance - entropic_PFR_conjecture_improv Entropic PFR, improved constants (10 and 11/2) after tau_minimizer_exists_rdist_eq_zero, rdist_triangle, exists_isUniform_of_rdist_eq_zero
- PFR_conjecture_improv_aux Documented declaration: PFR_conjecture_improv_aux
- PFR_conjecture_improv PFR with exponent 11 after PFR_conjecture_improv_aux, entropic_PFR_conjecture_improv
- KLDiv If
X, Yare twoG-valued random variables, the Kullback--Leibler divergence is defined asKL(X ‖ Y) := ∑ₓ 𝐏(X = x) log (𝐏(X = x) / 𝐏(Y = x)) - ProbabilityTheory.IdentDistrib.KLDiv_eq If
X'is a copy ofX, andY'is a copy ofY, thenKL(X' ‖ Y') = KL(X ‖ Y) - KLDiv_nonneg
KL(X ‖ Y) ≥ 0 - KLDiv_eq_zero_iff_identDistrib
KL(X ‖ Y) = 0if and only ifYis a copy ofX - KLDiv_of_convex Documented declaration: KLDiv_of_convex
- KLDiv_of_comp_inj If $f:G \to H$ is an injection, then $D_{KL}(f(X)\Vert f(Y)) = D_{KL}(X\Vert Y)$
- ProbabilityTheory.IndepFun.map_add_eq_sum The distribution of
X + Zis the convolution of the distributions ofZandXwhen these random variables are independent - ProbabilityTheory.IndepFun.map_add_singleton_eq_sum The distribution of
X + Zis the convolution of the distributions ofZandXwhen these random variables are independent - KLDiv_add_le_KLDiv_of_indep If $X, Y, Z$ are independent $G$-valued random variables, then $$D_{KL}(X+Z\Vert Y+Z) \leq D_{KL}(X\Vert Y).$$
- condKLDiv If $X,Y,Z$ are random variables, with $X,Z$ defined on the same sample space, we define $$ D_{KL}(X|Z \Vert Y) := \sum_z \mathbf{P}(Z=z) D_{KL}( (X|Z=z) \Vert Y).$$
- condKLDiv_eq Documented declaration: condKLDiv_eq
- condKLDiv_nonneg
KL(X|Z ‖ Y) ≥ 0 - ProbabilityTheory.IsUniform.measureReal_preimage_sub_zero Given two independent random variables
UandVuniformly distributed respectively onAandB, thenU = Vwith probability#(A ∩ B) / #A ⬝ #B - ProbabilityTheory.IsUniform.measureReal_preimage_sub Given two independent random variables
UandVuniformly distributed respectively onAandB, thenU = V + xwith probability# (A ∩ (B + x)) / #A ⬝ #B - PFR_conjecture_pos_aux Record positivity results that are useful in the proof of PFR
- PFR_conjecture_pos_aux'
- rdist_le_of_isUniform_of_card_sub_le Small doubling gives small self Ruzsa distance after rdist
- rdist_le_of_isUniform_of_doubling In characteristic 2, a uniform distribution on a set with doubling constant
Khas self Rusza distance at mostlog K - Fin.sum_univ_castSucc' TODO: Rename
Fin.sum_univ_castSucctoFin.sum_univ_eq_castSucc - Real.sum_mul_log_div_leq Documented declaration: sum_mul_log_div_leq
- Real.sum_mul_log_div_eq_iff_aux If equality holds in the previous bound, then $a_s=r\cdot b_s$ for every $s\in S$, for some constant $r\in \mathbb{R}$
- Real.sum_mul_log_div_eq_iff If equality holds in the previous bound, then $a_s=r\cdot b_s$ for every $s\in S$, for some constant $r\in \mathbb{R}$
- Submodule.exists_equiv_fst_sndModFst Given a submodule $E$ of $B \times F$, there is an equivalence $f : E \to B' \times F'$ given by the projections $E \to B$ and $E \to F$ "modulo" some $φ : B \to F$
- Submodule.finrank The dimension of a submodule
- MeasureTheory.lintegral_eq_sum TODO: Change RHS of
lintegral_fintype - MeasureTheory.setLIntegral_eq_sum TODO: Change RHS of
lintegral_finset - continuous_finiteMeasure_apply_of_isClopen The measure of any connected component depends continuously on the
FiniteMeasure - continuous_probabilityMeasure_apply_of_isClopen The probability of any connected component depends continuously on the
ProbabilityMeasure - ProbabilityMeasure.tendsto_iff_forall_apply_tendsto Probability measures on a finite space tend to a limit if and only if the probability masses of all points tend to the corresponding limits
- ProbabilityMeasure.tendsto_iff_forall_apply_tendsto_ennreal Probability measures on a finite space tend to a limit if and only if the probability masses of all points tend to the corresponding limits
- MeasureTheory.Measure.map_prod_comap_swap The law of $(X, Z)$ is the image of the law of $(Z,X)$
- ProbabilityTheory.cond_real_apply The axiomatic definition of conditional probability derived from a measure-theoretic one
- ProbabilityTheory.cond_isProbabilityMeasure_of_real The conditional probability measure of any finite measure on any set of positive measure is a probability measure
- ProbabilityTheory.IdentDistrib.fst_id The first projection in a product space with measure
μ.prod νis distributed likeμ - ProbabilityTheory.IdentDistrib.snd_id The second projection in a product space with measure
μ.prod νis distributed likeν - ProbabilityTheory.identDistrib_comp_left A function is identically distributed to itself composed with a measurable embedding of conull range
- ProbabilityTheory.identDistrib_comp_right A function is identically distributed to itself composed with a measurable embedding of conull range
- ProbabilityTheory.IdentDistrib.comp_left Composing identically distributed functions with a measurable embedding of conull range gives identically distributed functions
- ProbabilityTheory.IdentDistrib.comp_right Composing identically distributed functions with a measurable embedding of conull range gives identically distributed functions
- ProbabilityTheory.AEMeasurable.piMk Move to a different section?
- ProbabilityTheory.identDistrib_map A random variable is identically distributed to its pullbacks
- ProbabilityTheory.identDistrib_of_sum To show identical distribution of two random variables on a mixture of probability measures, it suffices to do so on each non-trivial component
- ProbabilityTheory.identDistrib_comp_fst A random variable is identically distributed to its lift to a product space (in the first factor)
- ProbabilityTheory.identDistrib_comp_snd A random variable is identically distributed to its lift to a product space (in the second factor)
- ProbabilityTheory.independent_copies For
X, Yrandom variables, one can find independent copiesX', Y'ofX, Y - ProbabilityTheory.independent_copies_two For
X, Yrandom variables, one can find independent copiesX', Y'ofX, Y - ProbabilityTheory.independent_copies' Let
Xᵢ : Ωᵢ → Sᵢbe random variables fori = 1,...,k - ProbabilityTheory.independent_copies3_nondep A version with exactly 3 random variables that have the same codomain
- ProbabilityTheory.independent_copies4_nondep A version with exactly 4 random variables that have the same codomain
- ProbabilityTheory.iIndepFun.finsets Documented declaration: finsets
- ProbabilityTheory.iIndepFun.finsets_comp Documented declaration: finsets_comp
- ProbabilityTheory.iIndepFun.finsets_comp' A variant of iIndepFun.finsets_comp where we conclude the independence of just two functions rather than an entire family
- ProbabilityTheory.indepFun_const Random variables are always independent of constants
- ProbabilityTheory.IndepFun.comp_right Composing independent functions with a measurable embedding of conull range gives independent functions
- ProbabilityTheory.iIndepFun_iff' Same as
iIndepFun_iffexcept that the functionf'returns measurable sets even on junk values - ProbabilityTheory.iIndepFun.pi If a family of functions
(i, j) ↦ f i jis independent, then the family of function tuplesi ↦ (f i j)ⱼis independent - ProbabilityTheory.iIndepFun.pi' If a family of functions
(i, j) ↦ f i jis independent, then the family of function tuplesi ↦ (f i j)ⱼis independent - ProbabilityTheory.iIndepFun.ae_eq TODO: a kernel version of this theorem
- ProbabilityTheory.Kernel.iIndepFun.finsets Documented declaration: finsets
- ProbabilityTheory.Kernel.iIndepFun.finsets_comp Documented declaration: finsets_comp
- ProbabilityTheory.Kernel.FiniteKernelSupport.reverse Reversing preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport The analogue of FiniteSupport for probability kernels
- ProbabilityTheory.Kernel.AEFiniteKernelSupport A kernel
κhas almost everywhere finite support wrt a measureμif, for almost every pointt, thenκ thas finite support - ProbabilityTheory.Kernel.local_support_of_finiteKernelSupport Finite kernel support locally implies uniform finite kernel support
- ProbabilityTheory.Kernel.finiteKernelSupport_of_finite_range Finite range implies finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.deterministic Deterministic kernels have finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.map maps preserve finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.comap comaps preserve finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.fst Projecting a kernel to first coordinate preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.snd Projecting a kernel to second coordinate preserves finite kernel support
- ProbabilityTheory.Kernel.aefiniteKernelSupport_of_cond Conditioning a kernel preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.swapRight Swapping a kernel right preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.prod Products preserve finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.compProd Composition-product preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.prodMkRight prodMkRight preserves finite kernel support
- ProbabilityTheory.Kernel.FiniteKernelSupport.prodMkLeft prodMkLeft preserves finite kernel support
- rdist_of_neg_le If
X, YareG-valued, thend[X;-Y] ≤ 3 d[X;Y] - kvm_ineq_I If
n ≥ 0andX, Y₁, ..., Yₙare jointly independentG-valued random variables, thenH[Y i₀ + ∑ i ∈ s, Y i; μ] - H[Y i₀; μ] ≤ ∑ i ∈ s, (H[Y i₀ + Y i; μ] - H[Y i₀; μ]) - kvm_ineq_II If
n ≥ 1andX, Y₁, ..., Yₙare jointly independentG-valued random variables, thend[Y i₀; μ # ∑ i ∈ s, Y i; μ] ≤ 2 * ∑ i ∈ s, d[Y i₀; μ # Y i; μ] - kvm_ineq_III_aux' strengthen the above lemma by not requiring
Xto be independent ofY,Z - kvm_ineq_III If
n ≥ 1andX, Y₁, ..., Yₙ$ are jointly independentG-valued random variables, thend[Y i₀, ∑ i, Y i] ≤ d[Y i₀, Y i₁] + 2⁻¹ * (H[∑ i, Y i] - H[Y i₁]) - ent_of_sum_le_ent_of_sum Let
X₁, ..., XₘandY₁, ..., Yₗbe tuples of jointly independent random variables (so theX's andY's are also independent of each other), and let `f : {1,..., l} → {1, - ent_sub_zsmul_le Let
X,Y,X'be independentG-valued random variables, withX'a copy ofX, and letabe an integer - ent_sub_nsmul_le Let
X,Y,X'be independentG-valued random variables, withX'a copy ofX, and letabe an integer - ent_of_sub_smul' Let
X,Y,X'be independentG-valued random variables, withX'a copy ofX, and letabe an integer - ent_sub_zsmul_sub_ent_le Let
X,Ybe independentG-valued random variables, and letabe an integer - ent_sub_nsmul_sub_ent_le Let
X,Ybe independentG-valued random variables, and letabe a natural number - ent_add_nsmul_sub_ent_le Let
X,Ybe independentG-valued random variables, and letabe a natural number - multiDist Let
X_[m] = (X₁, ..., Xₘ)be a non-empty finite tuple ofG-valued random variablesX_i - multiDist_copy If
X_ihas the same distribution asY_ifor eachi, thenD[X_[m]] = D[Y_[m]] - MeasureTheory.Measure.map_of_pi Move to Mathlib?
- multiDist_indep If
X_iare independent, thenD[X_{[m]}] = H[∑_{i=1}^m X_i] - \frac{1}{m} \sum_{i=1}^m H[X_i] - multiDist_nonneg We have
D[X_[m]] ≥ 0 - multiDist_of_perm If
φ : {1, ..., m} → {1, ...,m}is a bijection, thenD[X_[m]] = D[(X_φ(1), ..., X_φ(m))] - offDiag_sum The sum of
faway from the diagonal - multidist_ruzsa_I_indep To prove multidist_ruzsa_I, we first establish a special case when the random variables are defined on the same space and are jointly independent
- multidist_ruzsa_I Let
m ≥ 1, and letX_[m]be a tuple ofG-valued random variables - multidist_ruzsa_II Let
m ≥ 2, and letX_[m]be a tuple ofG-valued random variables - multidist_ruzsa_III' A version of multidist_ruzsa_III assuming independence
- multidist_ruzsa_III Let
Ibe an indexing set of sizem ≥ 2, and letX_[m]be a tuple ofG-valued random variables - multidist_ruzsa_IV Let
m ≥ 2, and letX_[m]be a tuple ofG-valued random variables - multidist_eq_zero If
D[X_[m]]=0, then for eachi ∈ Ithere is a finite subgroupH_i ≤ Gsuch thatd[X_i; U_{H_i}] = 0 - condMultiDist_of_inj Conditional multidistance is unchanged if we apply an injection to the conditioned variables
- condMultiDist_of_const Conditional multidistance against a constant is just multidistance
- condMultiDist_nonneg Conditional multidistance is nonnegative
- Finset.prod_mul A technical lemma: can push a constant into a product at a specific term
- ident_of_cond_of_indep A technical lemma: two different ways of conditioning independent variables gives identical distributions
- prob_nonzero_of_prod_prob_nonzero A technical lemma: if a product of probabilities is nonzero, then each probability is individually non-zero
- condMultiDist_eq If
(X_i, Y_i),1 ≤ i ≤ mare independent, thenD[X_[m] | Y_[m]] = H[∑ i, X_i | (Y_1, ..., Y_m)] - 1/m * ∑ i, H[X_i | Y_i] - condMultiDist_eq' If
(X_i, Y_i),1 ≤ i ≤ mare independent, thenD[X_[m] | Y_[m]] = ∑_{(y_i)_{1 ≤ i ≤ m}} P(Y_i=y_i ∀ i) D[(X_i | Y_i=y_i ∀ i)_{i=1}^m] - multiDist_chainRule Let
π : G → Hbe a homomorphism of abelian groups and letX_[m]be a tuple of jointly independentG-valued random variables - cond_multiDist_chainRule Let
π : G → Hbe a homomorphism of abelian groups - iter_multiDist_chainRule Let
mbe a positive integer - iter_multiDist_chainRule' Under the preceding hypotheses,
D[X_[m]] ≥ ∑ d, D[π_d(X_[m])| π_(d-1})(X_[m])] + I[∑ i, X_i : π_1(X_[m]) | π_1(∑ i, X_i)] - cor_multiDist_chainRule Let
Gbe an abelian group and letm ≥ 2 - MeasurableFinGroup We will frequently be working with finite additive groups with the discrete sigma-algebra
- multiRefPackage A structure that packages all the fixed information in the main argument
- multiTau If $(X_i)_{1 \leq i \leq m}$ is a tuple, we define its $\tau$-functional $$ \tau[ (X_i)_{1 \leq i \leq m}] := D[(X_i)_{1 \leq i \leq m}] + \eta \sum_{i=1}^m d[X_i; X^0].$$
- multiTauMinimizes A $\tau$-minimizer is a tuple $(X_i)_{1 \leq i \leq m}$ that minimizes the $\tau$-functional among all tuples of $G$-valued random variables
- multiTau_continuous If $G$ is finite, then $\tau$ is continuous
- multiTau_min_exists_measure If $G$ is finite, then a $\tau$-minimizer exists
- multiTau_min_exists If $G$ is finite, then a $\tau$-minimizer exists
- multiTau_min_sum_le If $(X_i)_{1 \leq i \leq m}$ is a $\tau$-minimizer, then $\sum_{i=1}^m d[X_i; X^0] \leq \frac{2m}{\eta} d[X^0; X^0]$
- sub_multiDistance_le Documented declaration: sub_multiDistance_le
- sub_condMultiDistance_le Documented declaration: sub_condMultiDistance_le
- sub_condMultiDistance_le' Documented declaration: sub_condMultiDistance_le'
- rhoMinusSet The set of possible values of $D_{KL}(X \Vert U_A + T)$, where $U_A$ is uniform on $A$ and $T$ ranges over $G$-valued random variables independent of $U_A$
- rhoMinus Documented declaration: rhoMinus
- rhoMinus_nonneg We have $\rho^-(X) \geq 0$
- rhoPlus For any $G$-valued random variable $X$, we define $\rho^+(X) := \rho^-(X) + \bbH(X) - \bbH(U_A)$
- rhoMinus_of_subgroup If $H$ is a finite subgroup of $G$, then $\rho^-(U_H) = \log |A| - \log \max_t |A \cap (H+t)|$
- rhoPlus_of_subgroup If $H$ is a finite subgroup of $G$, then $\rho^+(U_H) = \log |H| - \log \max_t |A \cap (H+t)|$
- rho We define $\rho(X) := (\rho^+(X) + \rho^-(X))/2$
- rho_of_uniform We have $\rho(U_A) = 0$
- rho_of_subgroup If $H$ is a finite subgroup of $G$, and $\rho(U_H) \leq r$, then there exists $t$ such that $|A \cap (H+t)| \geq e^{-r} \sqrt{|A||H|}$, and $|H|/|A| \in [e^{-2r}, e^{2r}]$
- rho_of_submodule If $H$ is a finite subgroup of $G$, and $\rho(U_H) \leq r$, then there exists $t$ such that $|A \cap (H+t)| \geq e^{-r} \sqrt{|A||H|}$, and $|H|/|A| \in [e^{-2r}, e^{2r}]$
- rho_continuous \rho(X)$ depends continuously on the distribution of $X$
- rhoMinus_of_sum If $X,Y$ are independent, one has $$ \rho^-(X+Y) \leq \rho^-(X)$$
- rhoPlus_of_sum If $X,Y$ are independent, one has $$ \rho^+(X+Y) \leq \rho^+(X) + \bbH[X+Y] - \bbH[X]$$
- rho_of_sum If $X,Y$ are independent, one has $$\rho(X+Y) \leq \rho(X) + \frac{1}{2}( \bbH[X+Y] - \bbH[X]).$$
- condRho We define $\rho(X|Y) := \sum_y {\bf P}(Y=y) \rho(X|Y=y)$
- condRhoMinus Average of rhoMinus along the fibers
- condRhoPlus Average of rhoPlus along the fibers
- condRho_of_translate For any $s\in G$, $\rho(X+s|Y)=\rho(X|Y)$
- condRho_of_injective If $f$ is injective, then $\rho(X|f(Y))=\rho(X|Y)$
- condRhoMinus_le $$ \rho^-(X|Z) \leq \rho^-(X) + \bbH[X] - \bbH[X|Z]$$
- condRhoPlus_le $$ \rho^+(X|Z) \leq \rho^+(X)$$
- condRho_le $$ \rho(X|Z) \leq \rho(X) + \frac{1}{2}( \bbH[X] - \bbH[X|Z])$$
- condRho_prod_le $$ \rho(X|Z) \leq \rho(X) + \frac{1}{2}( \bbH[X] - \bbH[X|Z])$$, conditional version
- rho_of_sum_le If $X,Y$ are independent, then $$ \rho(X+Y) \leq \frac{1}{2}(\rho(X)+\rho(Y) + d[X;Y]).$$
- condRho_of_sum_le If $X,Y$ are independent, then $$ \rho(X | X+Y) \leq \frac{1}{2}(\rho(X)+\rho(Y) + d[X;Y]).$$
- phi Given $G$-valued random variables $X,Y$, define $$ \phi[X;Y] := d[X;Y] + \eta(\rho(X) + \rho(Y))$$
- phiMinimizes Documented declaration: phiMinimizes
- phi_min_exists There exists a $\phi$-minimizer
- I_one_le $I_1\le 2\eta d[X_1;X_2]$
- rdist_add_rdist_eq $d[X_1;X_1]+d[X_2;X_2]= 2d[X_1;X_2]+(I_2-I_1)$
- I_two_le $I_2\le 2\eta d[X_1;X_2] + \frac{\eta}{1-\eta}(2\eta d[X_1;X_2]-I_1)$
- dist_le_of_sum_zero Documented declaration: dist_le_of_sum_zero
- dist_le_of_sum_zero_cond Documented declaration: dist_le_of_sum_zero_cond
- dist_le_of_sum_zero' Documented declaration: dist_le_of_sum_zero'
- dist_le_of_sum_zero_cond' Documented declaration: dist_le_of_sum_zero_cond'
- condRho_sum_le For independent random variables $Y_1,Y_2,Y_3,Y_4$ over $G$, define $S:=Y_1+Y_2+Y_3+Y_4$, $T_1:=Y_1+Y_2$, $T_2:=Y_1+Y_3$
- condRho_sum_le' For independent random variables $Y_1,Y_2,Y_3,Y_4$ over $G$, define $T_1:=Y_1+Y_2, T_2:=Y_1+Y_3, T_3:=Y_2+Y_3$ and $S:=Y_1+Y_2+Y_3+Y_4$
- dist_of_min_eq_zero' If $X_1, X_2$ is a $\phi$-minimizer, then $d[X_1;X_2] = 0$
- phiMinimizer_exists_rdist_eq_zero For
η ≤ 1/8, there exist phi-minimizersX₁, X₂at zero Rusza distance - rho_PFR_conjecture For any random variables $Y_1,Y_2$, there exist a subgroup $H$ such that $$ 2\rho(U_H) \leq \rho(Y_1) + \rho(Y_2) + 8 d[Y_1;Y_2].$$
- better_PFR_conjecture_aux0 If $|A+A| \leq K|A|$, then there exists a subgroup $H$ and $t\in G$ such that $|A \cap (H+t)| \geq K^{-4} \sqrt{|A||V|}$, and $|H|/|A|\in[K^{-8},K^8]$
- better_PFR_conjecture_aux Documented declaration: better_PFR_conjecture_aux
- better_PFR_conjecture Documented declaration: better_PFR_conjecture
- rdist_of_sums_ge' $$ d[X_1+\tilde X_1; X_2+\tilde X_2] \geq k - \frac{\eta}{2} ( d[X_1; X_1] + d[X_2;X_2] ).$$
- second_estimate $$ I_2 \leq 2 \eta k + \frac{2 \eta (2 \eta k - I_1)}{1 - \eta}.$$
- Mathlib.Tactic.RPowRing.Context The read-only state of the
RPowRingmonad - Mathlib.Tactic.RPowRing.Config Configuration for
ring_nf - Mathlib.Tactic.RPowRing.M Documented declaration: M
- Mathlib.Tactic.RPowRing.ExBase A monomial, which is a product of powers of
ExBaseexpressions, terminated by a (nonzero) constant coefficient - Mathlib.Tactic.RPowRing.ExProd A monomial, which is a product of powers of
ExBaseexpressions, terminated by a (nonzero) constant coefficient - Mathlib.Tactic.RPowRing.ExBase.toProd Embed an exponent (an
ExBase, ExProdpair) as anExProdby multiplying by 1 - Mathlib.Tactic.RPowRing.evalAtom Evaluates an atom, an expression where
ringcan find no additional structure - Mathlib.Tactic.RPowRing.evalMul Multiplies two monomials
va, vbtogether to get a normalized result monomial - Mathlib.Tactic.RPowRing.M.run Runs a tactic in the
RingNF.Mmonad, given initial data: *s: a reference to the mutable state ofring, for persisting across calls - Mathlib.Tactic.RPowRing.rpowRingTarget Use
rpow_ringto rewrite the main goal - Mathlib.Tactic.RPowRing.rpowRingLocalDecl Use
rpow_ringto rewrite hypothesish - Mathlib.Tactic.RPowRing.elabRPowRingConv Elaborator for the
rpow_ringtactic - refPackage A structure that packages all the fixed information in the main argument
- tau Documented declaration: tau
- ProbabilityTheory.IdentDistrib.tau_eq If $X'_1, X'_2$ are copies of $X_1,X_2$, then $\tau[X'_1;X'_2] = \tau[X_1;X_2]$
- TauMinimizes Property recording the fact that two random variables minimize the tau functional
- ProbabilityTheory.IdentDistrib.tauMinimizes If $X'_1, X'_2$ are copies of $X_1,X_2$, then $X_1, X_2$ minimize $\tau$ iff $X_1', X_2'$ do
- tau_min_exists_measure A pair of measures minimizing $\tau$ exists
- tau_minimizer_exists A pair of random variables minimizing $τ$ exists
- entropic_PFR_conjecture Entropic PFR (constants 11 and 6) after tau_minimizer_exists, tau_strictly_decreases, rdist_triangle, exists_isUniform_of_rdist_eq_zero
- PFR_conjecture_aux Covering lemma behind PFR after entropic_PFR_conjecture, rdist_le_of_isUniform_of_card_sub_le
- PFR_conjecture Polynomial Freiman-Ruzsa conjecture (characteristic 2) after PFR_conjecture_aux, PFR_conjecture_pos_aux'
- distance_ge_of_min Documented declaration: distance_ge_of_min
- distance_ge_of_min' Version of
distance_ge_of_minwith the measures made explicit - condRuzsaDistance_ge_of_min Documented declaration: condRuzsaDistance_ge_of_min
- sum_of_z_eq_zero Z_1+Z_2+Z_3= 0
- mutual_information_le_t_12 We have
I[Z_1 : Z_2 | W], I[Z_2 : Z_3 | W], I[Z_1 : Z_3 | W] ≤ 4m^2 η k - entropy_of_W_le We have $\bbH[W] \leq (2m-1)k + \frac1m \sum_{i=1}^m \bbH[X_i]$
- entropy_of_Z_two_le We have $\bbH[Z_2] \leq (8m^2-16m+1) k + \frac{1}{m} \sum_{i=1}^m \bbH[X_i]$
- mutual_of_W_Z_two_le We have $\bbI[W : Z_2] \leq 2(m-1) k$
- sum_of_conditional_distance_le We have $\sum_{i=1}^m d[X_i;Z_2|W] \leq 4(m^3-m^2) k$
- dist_of_U_add_le Documented declaration: dist_of_U_add_le
- k_eq_zero We have $k = 0$
- dist_of_X_U_H_le Suppose that $G$ is a finite abelian group of torsion $m$
- rdist_le_of_isUniform_of_card_add_le' A uniform distribution on a set with doubling constant
Khas self Rusza distance at mostlog K - torsion_PFR_conjecture_aux Suppose that $G$ is a finite abelian group of torsion $m$
- torsion_exists_subgroup_subset_card_le Every subgroup
Hof a finitem-torsion abelian groupGcontains a subgroupH'of order betweenkandmk, if0 < k < |H| - torsion_PFR Suppose that $G$ is an abelian group of torsion $m$ (not necessarily finite)
- IsShift A set
Ais a shift of a setBif it can be written asx + B - NotInCoset The property of two sets A, B of a group G not being contained in cosets of the same proper subgroup
- wlog_notInCoset Without loss of generality, one can move (up to translation and embedding) any pair A, B of non-empty sets into a subgroup where they are not in a coset
- torsion_free_doubling If
Gis torsion-free andX, YareG-valued random variables thend[X; 2Y] ≤ 5d[X; Y] - torsion_dist_shrinking If
Gis a torsion-free group andX, YareG-valued random variables andφ : G → 𝔽₂^dis a homomorphism thenH[φ ∘ X; μ] ≤ 10 * d[X; μ # Y; μ'] - app_ent_PFR' Let $G=\mathbb{F}_2^n$ and
X, YbeG-valued random variables such that \[\mathbb{H}(X)+\mathbb{H}(Y)> (20/\alpha) d[X;Y],\] for some $\alpha > 0$ - PFR_projection' Documented declaration: PFR_projection'
- PFR_projection Documented declaration: PFR_projection
- single_fibres Let $\phi : G\to H$ be a homomorphism and $A,B\subseteq G$ be finite subsets
- third_iso A version of the third isomorphism theorem: if G₂ ≤ G and H' is a subgroup of G⧸G₂, then there is a canonical isomorphism between H⧸H' and G⧸N, where N is the preimage of H' in G
- weak_PFR_asymm_prelim Documented declaration: weak_PFR_asymm_prelim
- WeakPFRAsymmConclusion Separating out the conclusion of
weak_PFR_asymmfor convenience of induction arguments - not_in_coset The property of two sets A,B of a group G not being contained in cosets of the same proper subgroup
- dimension_of_shift In fact one has equality here, but this is trickier to prove and not needed for the argument
- weak_PFR_asymm Documented declaration: weak_PFR_asymm
- weak_PFR Documented declaration: weak_PFR
- weak_PFR_int Weak PFR over the integers after weak_PFR, weak_PFR_asymm, ProbabilityTheory.setRuzsaDist_le
- weak_PFR_int_sumset Weak PFR from a sumset hypothesis after weak_PFR_int
- Marton.pfr_conjecture@PFRPalomar/Challenge.lean Marton's conjecture in characteristic 2,
[GGMT], Theorem 1.2 - Marton.pfr_conjecture_nine@PFRPalomar/Challenge.lean Marton's conjecture in characteristic 2 with exponent 9,
[L], main theorem - Marton.torsion_pfr_conjecture@PFRPalomar/Challenge.lean Marton's conjecture in abelian groups of bounded torsion,
[GGMT2], Theorem 1.1 - Marton.weak_pfr_int@PFRPalomar/Challenge.lean Weak Marton's conjecture over the integers,
[GGMT], Theorem 1.3 - Marton.homomorphism_pfr@PFRPalomar/Challenge.lean The homomorphism form of Marton's conjecture,
[GGMT], Corollary 1.4 - Marton.approx_hom_pfr@PFRPalomar/Challenge.lean The approximate homomorphism form of Marton's conjecture,
[GGMT], Corollary 1.5