Evidence · Case 08 · Science
Penzias and Wilson’s 1965 detection of the cosmic microwave background
One exhibit from the free evidence repository at apologetics.pro.
Sources
Arno Penzias and Robert Wilson, “A Measurement of Excess Antenna Temperature at 4080 Mc/s,” Astrophysical Journal, 1965. - American Physical Society, “Holmdel Horn Antenna” historic site.
Objections & responses
- The CMB is the afterglow of the universe becoming transparent about 380,000 years after the Big Bang. It tells us nothing about t = 0 or whether there was anything before.
Correct. The microwave background confirms a hot, dense early state and rules out steady-state models; it does not reach the beginning itself. Start here means the start of the current expansion phase. The stronger claim about an absolute beginning rests on the singularity theorems and on the Borde-Guth-Vilenkin theorem, which the Atheism case cites, and even those leave the quantum-gravity regime open. What the CMB settles is that the universe has a history and a finite age, which is what the older eternal-universe picture denied.
- The Big Bang is the beginning of the current expansion, not necessarily of everything. Inflation, bounce models, and quantum gravity approaches all allow a past before it. Isn’t “the universe had a beginning” just one reading?
That is accurate and worth saying plainly. The standard model traces the observable universe back to a hot, dense state about 13.8 billion years ago; what happened at or before the Planck time is not known, and several models extend the past. What can be said with confidence is that the observable universe has a finite age and that eternal-past models face the Borde-Guth-Vilenkin theorem’s constraint on average expansion. The careful version of the claim is that the observable universe has a finite past and that models with an infinite past face serious theoretical obstacles, not that physics has closed the question.