#include <boost/multiprecision/cpp_dec_float.hpp>
#include <iostream>

int main()
{
	using namespace boost::multiprecision;

	typedef number<cpp_dec_float<10000> > number_t;

	number_t earth_age = 6000; // years
	number_t T = earth_age * 31557600; // seconds per Julian year
	number_t g = 9.81; // m/s^2
	number_t c = 299792458; // m/s

	number_t phi = (g * T) / c;
	number_t beta = tanh(phi);
	number_t inv_gamma = sqrt(1.0 - (beta*beta));

	std::cout << std::setprecision(std::numeric_limits<number_t>::max_digits10);
	std::cout << "beta = " << beta << std::endl << std::endl;
	std::cout << "inv_gamma = " << inv_gamma << std::endl << std::endl;

	number_t earth_radius = 6371 * 1000; // meters
	number_t flat_earth = 2 * earth_radius * inv_gamma;

	std::cout << std::setprecision(10);
	std::cout << "flat earth thickness = " << flat_earth << " meters" << std::endl << std::endl;


	return 0;
}