Personalized Quantum Mechanics Building Long Sleeve T-Shirt. Quantum Mechanics Building text with a floor plan and the you are here arrows pointing to 2 different spots. Particles can be in two different places simultaneously. Can You? A humorous physics design for your favorite student, teacher, engineer or scientist at birthdays and holidays. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL