I am not sure where to post this, so I put it here:
I had never received any down votes on any of any of my answers, until today, and I got 7. They were all in the same time frame, and certainly by the same user. Lets call him Bob. (since that is not the name of any user I know. I know who bob actually is, but I won't type it for now) The reason I am posting this is because:
6 of the downvotes were for answers accepted by the OP where "Bob" had also posted an answer. Bob's answers were generally more sophisticated mathematically, but the OP chose mine for whichever reasons. I have no other accepted answers where Bob also posted an answer. (Not to mention, Bob was online, and Bob's down vote counter increased during this time)
I feel these were spiteful down votes, and were only given because "Bob" did not like the fact that my answer was chosen over his. I do not believe any of these answers deserved down votes, except possibly one.
The reputation is a non-issue, down votes don't really affect it. What bothers me is the action of down voting answers where your answer was not chosen. This is not a valid reason, and does not mean the other answer was bad. This in principle should not be allowed, and I would think that more senior users would know better.