Finding homomorphism from finite abelian group G
Clash Royale CLAN TAG#URR8PPP
up vote
2
down vote
favorite
Does there exists a homomorphism from a finite abelian group G to R*(Set of reals under multiplication) ?
My try:
Suppose f be non trivial homomorphism from G to R*. Since f(G) is subgroup of R* and G is finite implies R* has a finite subgroup which is other than non trivial. Now R* has only finite subgroup 1,-1 this implies f(G)= 1,-1 .Also from property of homomorphism order of f(G) divides order of G this will conclude that order of G is even. Now I am stuck after this.How to proceed?
abstract-algebra group-homomorphism
 |Â
show 2 more comments
up vote
2
down vote
favorite
Does there exists a homomorphism from a finite abelian group G to R*(Set of reals under multiplication) ?
My try:
Suppose f be non trivial homomorphism from G to R*. Since f(G) is subgroup of R* and G is finite implies R* has a finite subgroup which is other than non trivial. Now R* has only finite subgroup 1,-1 this implies f(G)= 1,-1 .Also from property of homomorphism order of f(G) divides order of G this will conclude that order of G is even. Now I am stuck after this.How to proceed?
abstract-algebra group-homomorphism
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55
 |Â
show 2 more comments
up vote
2
down vote
favorite
up vote
2
down vote
favorite
Does there exists a homomorphism from a finite abelian group G to R*(Set of reals under multiplication) ?
My try:
Suppose f be non trivial homomorphism from G to R*. Since f(G) is subgroup of R* and G is finite implies R* has a finite subgroup which is other than non trivial. Now R* has only finite subgroup 1,-1 this implies f(G)= 1,-1 .Also from property of homomorphism order of f(G) divides order of G this will conclude that order of G is even. Now I am stuck after this.How to proceed?
abstract-algebra group-homomorphism
Does there exists a homomorphism from a finite abelian group G to R*(Set of reals under multiplication) ?
My try:
Suppose f be non trivial homomorphism from G to R*. Since f(G) is subgroup of R* and G is finite implies R* has a finite subgroup which is other than non trivial. Now R* has only finite subgroup 1,-1 this implies f(G)= 1,-1 .Also from property of homomorphism order of f(G) divides order of G this will conclude that order of G is even. Now I am stuck after this.How to proceed?
abstract-algebra group-homomorphism
asked Aug 20 at 10:27
Vaibhav Kalia
204
204
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55
 |Â
show 2 more comments
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55
 |Â
show 2 more comments
active
oldest
votes
active
oldest
votes
active
oldest
votes
active
oldest
votes
active
oldest
votes
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2888628%2ffinding-homomorphism-from-finite-abelian-group-g%23new-answer', 'question_page');
);
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
That's pretty much there is: for a non-trivial homomorphism to exists, the group has to have a subgroup of index two and thus it has even order...
â DonAntonio
Aug 20 at 10:37
@DonAntonio correct me if I am wrong sir but I think only finite subgroup of R* other than trivial is 1,-1
â Vaibhav Kalia
Aug 20 at 10:37
@Va That is correct.
â DonAntonio
Aug 20 at 10:38
@DonAntonio How to define a non trivial homomorphism from G to 1,-1
â Vaibhav Kalia
Aug 20 at 10:39
@VaibhavKalia Can you find a homomorphism to $mathbbZ/2mathbbZ$ from some particular groups you are familiar with?
â Santana Afton
Aug 20 at 11:55