Branches of science you have to ignore to believe in young Earth creationism
“”The fact that young earth creationists have to form a committee for six years to argue against a scientific principle, is evidence in and of itself that the earth is old.
|—Greg Neyman, old-earth creationist|
Creationism is fundamentally incompatible with large swathes of science. To be completely honest, you pretty much need to willfully ignore the entirety of science, down to the level of applying basic logic to the world; but if "all of them" is too broad vague for you:
- Astrophysics - specifically things such as the speed of light which generates the starlight problem. In order for the universe (YEC usually has the entire universe pop into existence, rather than just the planet) to be seen, either the speed of light has to be changing or light had to have started en route to Earth already. The former is not supported by modern science or any observational evidence, and even semi-coherent theories regarding an anisotropic synchrony convention or c-decay can't account for the massive change needed. The latter is a case of special pleading and can lead to Last Thursdayism.
- The Cosmic Microwave Background (CMB) - a background level of very cold, low frequency radiation, predicted to exist by the "Big Bang" model and discovered and researched intensively throughout the latter half of the 20th century.
- General physics
- Mechanics - including Newtonian mechanics with gravity
- Nuclear physics - the decay rates of certain isotopes are known and are used in radiometric dating. YEC beliefs often require these well established rates to change by, for lack of a better term, stuff.
- Transport phenomena
- Fluid mechanics (momentum transfer) is pretty much incompatible with the idea of a global flood.
- Heat transfer is pretty much incompatible with all the variations of ideas that require water under earth's crusts, or in case of radiative heat transfer, White hole cosmology and anything that involves different speed of light or radioactive meterial giving radiation at a significantly different rate.
- Mass transfer would also have to be ignored, due to phenomena such as diffusion of impurities or crystal/sediment formation.
- Physical chemistry
- Reaction kinetics - the rate that amino acids undergo racemisation (conversion to an equal mix of stereoisomers) is a well known process that occurs at a specific rate. It can therefore be used as a dating method and has shown biological molecules to be far older than 6000 years.
- Thermodynamics - all the laws of thermodynamics are violated in a creation event.
- Materials Science
- Tribology - is the study of wear and friction in materials in relative motion to each other. The well-documented rates and mechanisms of wear and erosion preclude the rapid formation of geological features, such as the Grand Canyon, as claimed by young Earth creationists.
- General biology
- Botany - particularly Dendrochronology, which is considered not just accurate give or take a few years, but accurate to the year, as each layer of a tree represents one year. By overlapping patterns, dendrochronology clearly goes back tens of thousands of years at least, long before most YEC proponents say the universe even existed. (Some try to counter that trees can grow two rings in a year, which is true for some species on occasion, but other long-living species, like the bristlecone pine, are known to actually skip rings every once in a while. Even if we only had species that could occasionally grow extra rings, YEC would require a consistent rate of two to three rings per year since creation.)
- Pharmacology - disease causing bacteria and viruses mutate and become immune to our attempts at destroying or immunizing against them. This is one of the more powerful and very much real observations of evolution that supposedly doesn't happen in the YEC belief. See MRSA drug resistance.
- Molecular biology
- Genetics - the discovery of the genetic code was one of the biggest confirmations of evolution by natural selection and went a great way to explain the empirical observations such as Mendel's Laws. The supposed dichotomy between "macroevolution" and "microevolution" can only exist if there are two forms of DNA, one that mutates and another that is immune from mutation - otherwise there is no barrier between the two. This is not borne out in observations.
- Biochemistry (Although Michael Behe begs to differ, he's not openly advocating young earth)
- Computer Science
- Cellular automata applications - self-reproducing molecules are cellular automata which combine themselves using a few simple rules to cause emergent properties. If cellular automata (which are Turing-complete) are ignored, the entire corpus of computability theory has to be ignored.
- Evolutionary computation - The theory of evolution is not reserved only to biological lifeforms. Just like how computers can simulate physics, chemistry, climate and other natural phenomena, they also can simulate evolutionary processes. By abstracting the principes of evolution, it's possible to "breed" efficient problem solving algorithms. There's an entire branch on artificial intelligence dedicated to study the optimization and learning applications of evolution. Here's an example of the creation of a tetris playing code
 Planetary science
- Geomorphology - uplift causes mountain ranges to form, a process that can be observed to occur at a fixed rate.
- Plate tectonics - that tectonic plates are known to move at a certain rate, postulating that some pieces of land were one connected at some point - something observed and confirmed in the fossil record.
- Petrology - rocks and crystal structures that take considerably longer than 6000 years to form.
- Stratigraphy - rock layering through sedimentation - although creationists bizarrely like to attribute this to the Global Flood, even though a single event wouldn't explain layering.
- Fossil fuels - the estimated biomass required to form all the coal and oil underground suggest at least millions of years to accumulate it.
- Palaeontology - self explanatory. There is a massive amount of evidence from palaeontology that only works and makes sense given a very, very old Earth.
- Metrology - Modern measurement defines distance based on speed of light and time based on radioactive decay. If radiometric dating and starlight problem are to be said invalid, one might as well throw out these definitions.
The following are more humanities than science, but they are included for the sake of completion, and to emphasize how ridiculous YEC is. Each of these assumes, or actually requires, more than six thousand years of human history—a historian could probably identify kings older than that, or an archaeologist could present artifacts more than six thousand years old.
Is there anything left? Yes! There are two final things!