At least 1 hour before serving, freeze 6 to 8 martini glasses.
Combine the gin, pomegranate juice, lime juice and simple syrup in a large pitcher. Fill a cocktail shaker half full of ice, pour in the gimlet mixture until the shaker is 3/4 full and shake for 15 seconds. Pour into the frozen glasses and garnish each glass with a teaspoon of pomegranate seeds and a slice of lime.
*For the simple syrup, combine 1 cup of sugar with 1 cup of water in a small saucepan and heat until the sugar dissolves completely. Set aside to cool or refrigerate for up to 2 weeks.