This is the scientific/archaeological/historical case against the actual existence of a human being answering the religious description of Jesus Christ:
1. At the time and place where he is said to have lived, there were not sufficient records to establish the identity of individual humans. Proving that Jews lived in what is now known as Israel in the time period JC is said to have lived is not scientific, historical or archaeological proof that one such Jew was JC, a man who died at the age of 33.
2. At the time JC is said to have lived, virtually every platitude he spoke was a previously-articulated idea of another religion. This is extremely detrimental to any scientific, archaeological or historical claim of his actual existence that is based on such things as allegedly contemporaneous writings of a religious or philosophical nature.
For the sake of comparison, when Buddha is said to have lived, there (apparently) was no previously-existing religious or philosophical theory of reincarnation or nirvana. The fact that such ideas emerged in human history at or about the time Buddha is claimed to have actually lived certainly does not prove that an individual answering his description actually did so, but it doesn't disprove it, either.
In the case of JC, a detached analysis of the known facts based only on cold rationality would led to the conclusion that a collection of myths, platitudes and ideas already in existence were cobbled together, and that the JC myth was created to further their promotion.
3. JC had no descendents, according to the myth, and held no position of power. We know that Ramses I existed because we know that he fathered Ramses II and that he was the pharaoh of Egypt during a certain time in the distant past. This is typical of archaeology: we are able to tell that, say, 10,000 humans lived at a building site that erected the pharaoh's pyramid/tomb, but apart from the pharaoh himself, we can't identify any of those 10,000 men, women and children by name. As time marches forward, we see various means of identification of others in positions of power around a ruler, but until about the 15th century at the earliest, we cannot identify individual humans of the lower class in virtually any society.