Can light go back to its source and become what it was before it got turned into energy?
Can something diminish back to what it was before it grew into what it would grown into?
Can something that has exploded turn back into what it was before the explosion occurred?
Can you take something that is destroyed and turn it into something it was before destruction?
To cut that short, Can you take everything back to its original state and still have everything accounted for?
radioactive decay over the years would have to be able to have been undone
energy would have to return to its source and become what it was beforehand
children would shrink back into a fertilized egg and then become nothing again
This assumes only one linear progression of cause and effect.
It assumes a whole lot more than that. The second law of thermodynamics; entropy. Only a few types of systems are assumed to be locally reversible. The clear progression of cause and effect is not the answer here. For the system to reverse there must be a cause for the reversal. So reverse progression is a separate series of causes and effects.