FP0021

prime_field_zero_has_no_multiplicative_inverse

Alpha v34 independently verified · alpha_closed; checked-use authorized; not Stable

Zero has no product equal to one; this follows from multiplication, not from the inverse definition's guard.

Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved.

Exact expanded first-order arithmetic statement

forall p b. (~((p) = 1) /\ forall pfa_factor_left_zero_inverse_domain pfa_factor_right_zero_inverse_domain. (p) = pfa_factor_left_zero_inverse_domain * pfa_factor_right_zero_inverse_domain -> pfa_factor_left_zero_inverse_domain = 1 \/ pfa_factor_right_zero_inverse_domain = 1) -> ~(((exists pfa_gap_zero_inverseleft. pfa_gap_zero_inverseleft + S (0) = (p)) /\ (((exists pfa_gap_zero_inverseright. pfa_gap_zero_inverseright + S (b) = (p)) /\ ((((exists pfa_gap_zero_inverseresultbound. pfa_gap_zero_inverseresultbound + S (1) = (p)) /\ ((exists pfa_offset_left_zero_inverseresultcongruence pfa_offset_right_zero_inverseresultcongruence. ((0) * (b)) + (p) * pfa_offset_left_zero_inverseresultcongruence = (1) + (p) * pfa_offset_right_zero_inverseresultcongruence)))))))))

Constructive proof overview

Generated structural guide

Zero has no product equal to one; this follows from multiplication, not from the inverse definition's guard.

The unchanged tactic script uses 3 declared prerequisites and contains 24 exact native proof lines.

Alpha v34 checked-use · first admitted v31 · independently kernel and Lean verified; not Stable

Proof neighborhood

Direct dependencies

FP0019 prime_field_multiply_zero_left FP000D prime_field_multiply_functional succ_ne_zero Stable theorem; checked-use authorized

Direct dependents

FP0022 prime_field_inverse_output_nonzero

Formal native tactic body

Dependencies are introduced as named hypotheses before line 1. Local theorem links identify exact declared prerequisites. This exact body belongs to a complete independently kernel-checked constructive proof bundle and has Alpha checked-use authority; it does not imply Stable membership.

Read the argument

Proof checkpoints

24 script commands · 5 reading checkpoints · 2 local claims

This is a reading aid, not a new proof or a proof-tree certificate. Checkpoint groups are consecutive commands, not inferred branch boundaries. Every step links to the preserved script.

Named ingredients (2)
prime field multiply zero leftprime field multiply functional
01Fix variables and assumptionsL1–4

Work with arbitrary variables or the premises of the current implication.

  1. L1
    intro p
  2. L2
    intro b
  3. L3
    intro hp
  4. L4
    intro hm
02Establish hcopyL5–6

Establish this local claim before using it. It is not an additional assumption.

  1. L5
    have hcopy : ((exists pfa_gap_zero_inverse_copyleft. pfa_gap_zero_inverse_copyleft + S (0) = (p)) /\ (((exists pfa_gap_zero_inverse_copyright. pfa_gap_zero_inverse_copyright + S (b) = (p)) /\ ((((exists pfa_gap_zero_inverse_copyresultbound. pfa_gap_zero_inverse_copyresultbound + S (1) = (p)) /\ ((exists pfa_offset_left_zero_inverse_copyresultcongruence pfa_offset_right_zero_inverse_copyresultcongruence. ((0) * (b)) + (p) * pfa_offset_left_zero_inverse_copyresultcongruence = (1) + (p) * pfa_offset_right_zero_inverse_copyresultcongruence))))))))
  2. L6
    exact hm
03Separate the logical casesL7–8

Follow the explicit conjunction, disjunction, witness, or contradiction step recorded below.

  1. L7
    cases hcopy
  2. L8
    cases hcopy_right
04Establish hbadL9–18

Establish this local claim before using it. It is not an additional assumption. The following proof commands apply prime field multiply functional.

  1. L9
    have hbad : 1 = 0
  2. L10
    specialize prime_field_multiply_functional (p)
  3. L11
    specialize prime_field_multiply_functional (0)
  4. L12
    specialize prime_field_multiply_functional (b)
  5. L13
    specialize prime_field_multiply_functional (1)
  6. L14
    specialize prime_field_multiply_functional (0)
  7. L15
    apply prime_field_multiply_functional
  8. L16
    exact hm
  9. L17
    specialize prime_field_multiply_zero_left (p)
  10. L18
    specialize prime_field_multiply_zero_left (b)
05Use earlier factsL19–24

Instantiate or apply named facts and discharge the corresponding proof obligations.

  1. L19
    apply prime_field_multiply_zero_left
  2. L20
    exact hp
  3. L21
    exact hcopy_right_left
  4. L22
    specialize succ_ne_zero (0)
  5. L23
    apply succ_ne_zero
  6. L24
    exact hbad

Library-wide reading audit

Original exact command ledger · 24 lines
  1. 0001intro p
  2. 0002intro b
  3. 0003intro hp
  4. 0004intro hm
  5. 0005have hcopy : ((exists pfa_gap_zero_inverse_copyleft. pfa_gap_zero_inverse_copyleft + S (0) = (p)) /\ (((exists pfa_gap_zero_inverse_copyright. pfa_gap_zero_inverse_copyright + S (b) = (p)) /\ ((((exists pfa_gap_zero_inverse_copyresultbound. pfa_gap_zero_inverse_copyresultbound + S (1) = (p)) /\ ((exists pfa_offset_left_zero_inverse_copyresultcongruence pfa_offset_right_zero_inverse_copyresultcongruence. ((0) * (b)) + (p) * pfa_offset_left_zero_inverse_copyresultcongruence = (1) + (p) * pfa_offset_right_zero_inverse_copyresultcongruence))))))))
  6. 0006exact hm
  7. 0007cases hcopy
  8. 0008cases hcopy_right
  9. 0009have hbad : 1 = 0
  10. 0010specialize prime_field_multiply_functional (p)
  11. 0011specialize prime_field_multiply_functional (0)
  12. 0012specialize prime_field_multiply_functional (b)
  13. 0013specialize prime_field_multiply_functional (1)
  14. 0014specialize prime_field_multiply_functional (0)
  15. 0015apply prime_field_multiply_functional
  16. 0016exact hm
  17. 0017specialize prime_field_multiply_zero_left (p)
  18. 0018specialize prime_field_multiply_zero_left (b)
  19. 0019apply prime_field_multiply_zero_left
  20. 0020exact hp
  21. 0021exact hcopy_right_left
  22. 0022specialize succ_ne_zero (0)
  23. 0023apply succ_ne_zero
  24. 0024exact hbad