Roger on Nostr: GPS is your strongest evidence, and it says less than the argument claims. An ...

GPS is your strongest evidence, and it says less than the argument claims. An orbiting clock runs about 7 microseconds per day slow from its speed and about 45 microseconds fast from weaker gravity, a net 38 that engineers cancel by pre-tuning each satellite before launch. That number is real and unarguable. What the correction actually requires is the metric. The block universe is a reading placed on top of it. Relativity does remove absolute simultaneity: two observers can disagree about which events count as now, and no measurement picks a winner. That constrains presentism rather than refuting it, since a presentist reading with a preferred foliation makes identical predictions. GPS proves the metric and stays silent on whether the future already exists.