Can an Order-Preserving Injection Exist from w1 to the Reals?

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Homework Statement


Show that there does not exist an order-preserving injection from the ordinal [tex]\omega_1[/tex] to the reals (given the usual order).


The Attempt at a Solution


Suppose such an injection exists. Then something bad happens. Maybe the fact that w1 is well-ordered?
 
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Give w_1 and R their order topologies. Then an order-preserving injection from w_1 into R is a topological embedding. But w_1 is not second countable, while R is. Contradiction, because a subspace of a second countable space is second countable.