{"product_id":"secundar-the-second-referee-mug","title":"Secundar, the Second Referee Mug","description":"\u003cp\u003eGauge freedom: A → A + ∇χ, φ → φ − ∂χ\/∂t leaves E and B unchanged. Gauge transformations change nothing physical.\u003c\/p\u003e\n\u003cp\u003eThe joke: Reviewer 2's requested revisions: lots of work, zero observable difference. The slogan on the mug reads \u003cstrong\u003ePURE GAUGE. NOTHING PHYSICAL CHANGED.\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eSource: J. D. Jackson, Classical Electrodynamics, 3rd ed. (Wiley, 1999), §6.3; H. Weyl, Z. Phys. 56, 330 (1929).\u003c\/p\u003e","brand":"Printify","offers":[{"title":"11oz","offer_id":50976168476775,"sku":"90929541355815431702","price":21.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/13782256405507959175_2048.jpg?v=1793683608","url":"https:\/\/pixelatedphysics.com\/pt\/products\/secundar-the-second-referee-mug","provider":"Pixelated Physics","version":"1.0","type":"link"}