Metamath Proof Explorer


Theorem rrhf

Description: If the topology of R is Hausdorff, Cauchy sequences have at most one limit, i.e. the canonical homomorphism of RR into R is a function. (Contributed by Thierry Arnoux, 2-Nov-2017)

Ref Expression
Hypotheses rrhf.d D=distRB×B
rrhf.j J=topGenran.
rrhf.b B=BaseR
rrhf.k K=TopOpenR
rrhf.z Z=ℤModR
rrhf.1 φRDivRing
rrhf.2 φRNrmRing
rrhf.3 φZNrmMod
rrhf.4 φchrR=0
rrhf.5 φRCUnifSp
rrhf.6 φUnifStR=metUnifD
Assertion rrhf φℝHomR:B

Proof

Step Hyp Ref Expression
1 rrhf.d D=distRB×B
2 rrhf.j J=topGenran.
3 rrhf.b B=BaseR
4 rrhf.k K=TopOpenR
5 rrhf.z Z=ℤModR
6 rrhf.1 φRDivRing
7 rrhf.2 φRNrmRing
8 rrhf.3 φZNrmMod
9 rrhf.4 φchrR=0
10 rrhf.5 φRCUnifSp
11 rrhf.6 φUnifStR=metUnifD
12 eqid topGenran.=topGenran.
13 1 12 3 4 5 6 7 8 9 10 11 rrhcn φℝHomRtopGenran.CnK
14 uniretop =topGenran.
15 eqid K=K
16 14 15 cnf ℝHomRtopGenran.CnKℝHomR:K
17 13 16 syl φℝHomR:K
18 nrgngp RNrmRingRNrmGrp
19 ngpxms RNrmGrpR∞MetSp
20 7 18 19 3syl φR∞MetSp
21 xmstps R∞MetSpRTopSp
22 3 4 tpsuni RTopSpB=K
23 20 21 22 3syl φB=K
24 23 feq3d φℝHomR:BℝHomR:K
25 17 24 mpbird φℝHomR:B