Personalized Quantum Mechanics Building Long Sleeve Creeper. 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. For chillier weather, dress baby in this soft long sleeve creeper in a great fitting 1x1 baby rib. 5.0 oz., 100% combed ringspun cotton, 1x1 baby rib. White is sewn with 100% cotton thread, Flatlock seams, Double-needle stitched rib binding on neck, shoulders, sleeves and leg openings,Reinforced three-snap closure on binding.