I bet you could do some trig by observing distances and angles of known objects around the tower and comparing it to the size of the traveler. I think your biggest issue with your calculations are that they are assuming your clearly coffee stain picture is to scale. If I know anything, it's that there have been a dozen different images of the traveler, the city, and Earth at different scales. As far as what electroweak material is, it's likely relating to the electroweak force, a combination of the electromagnetic and weak fundemental forces (I'd say it's worth noting that the description says it [i]feels[/i] like lead, neutronium and electroweak, but I'll leave you to decide if that's metaphor or not). The electroweak force only arises when temperatures are high enough (10^15, according to Wiki), and can lead the the formation of massive (read "has mass," the opposite of "massless") subatomic particles: the W and Z gauge bosons, which are responsible for the weak force and interact heavily with the Higgs field. That last bit might be a clue. It's proposed that most mass of an object comes from the innumerable virtual bosons exchanging energy between quarks (which make up the protons and neutrons in atoms). These particles have mass, which indicate they interact with the Higgs field, which is said to give mass to particles. Perhaps "electroweak" in this case is indicating a larger than rational presence of exotic bosons (species of bosons that are created when the electromagnetic and weak forces combined as described earlier) which may interact more heavily with the Higgs field, fitting, in a rough not-entirely-scientific way, with the inclusion of known heavy particles of lead and neutronium. Just my guess.