I think it is possible, but currently thought impossible with our current way of looking at things.
Regarding does the past exist in some form, I believe it does. Soundwaves for example do not cease to exist, they just get smaller and smaller over time. If you had a microphone type device that was so sensitive to sound and could amplify it, and could somehow block out other sounds, you could hear into the past.
You can also look into the past everyday, many hundreds of thousands of years even! Just look at the sky at night. Those stars you see are NOT how they look now, that light has took thousands of light years to get here and what we are seeing is the star those years ago.
It is possible the star does not even exist now, but we can see it still.